000
FXUS66 KLOX 060536 AAA
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1035 PM PDT SUN SEP 5 2010
...UPDATED AVIATION DISCUSSION...
.SYNOPSIS...
TEMPERATURES WILL CONTINUE TO DROP THROUGH WEDNESDAY AS ANOTHER
SERIES OF UPPER LEVEL LOW PRESSURE SYSTEMS MOVE THROUGH THE WEST
COAST. NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL EXPAND INTO THE
VALLEYS TONIGHT...AND WILL POSSIBLY REACH THE COASTAL SLOPES BY MID
WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-WED)...FIRST OF ALL...WE APOLOGIZE FOR ANY
INCONVENIENCE FOR THE DELAY IN RECEIVING PRODUCTS THIS AFTERNOON.
THERE WAS A COMMS ISSUE THAT WAS SOLVED LATE THIS AFTERNOON.
TEMPERATURES WERE DOWN SIGNIFICANTLY AS EXPECTED TODAY WITH MOST
INLAND AREAS LOWER 7 TO 10 DEGREES...WHILE THE COASTAL AREAS WERE
DOWN 3 TO 5 DEGREES FOR THE MOST PART.
THE UPPER LVL RIDGE WILL CONTINUE TO BREAKDOWN OVERNIGHT AS A BROAD
TROUGH BEGINS TO PUSH SOUTH FROM THE PAC NW. THERE WILL BE AN
OVERALL COOLING TREND ON MONDAY...ESPECIALLY FOR AREAS S OF POINT
CONCEPTION WHERE A CATALINA EDDY SHOULD DEVELOP. THE COMBINATION OF
THIS EDDY BRINGING A DEEPER MARINE LAYER OVERNIGHT AND STRONGER
ONSHORE GRADIENTS FOR LAX-DAG AND LAX-BFL SHOULD TRANSLATE INTO AN
ADDITIONAL 5 TO 10 DEGREES OF COOLING WITH LA/VTU COUNTY HIGHS ONLY
REACHING THE UPPER 70S TO MID 80S. LATEST AMDAR SOUNDING NEAR KLAX
INDICATED THE MARINE LAYER AROUND 1000 FT DEEP THIS EVENING. THE
EDDY SHOULD HELP TO DEEPEN AND WEAKEN THE INVERSION A BIT. THIS
SHOULD ALLOW SOME PATCHY LOW CLOUDS AND FOG TO CREEP INTO THE
COASTAL VALLEYS OVERNIGHT. AREAS N OF POINT CONCEPTION COULD SEE
SOME PATCHY LOW CLOUDS DEVELOP NEAR LOMPOC TO SANTA MARIA...AND
POSSIBLY SANTA YNEZ OVERNIGHT...HOWEVER 950MB-850MB WIND FLOW FROM
THE NAM-WRF WILL BE OUT OF THE EAST TOMORROW MORNING...LIKELY DUE TO
PASSING COLD FRONT ACROSS NEVADA. THIS SHOULD BRING A FEW DEGREES OF
WARMING ACROSS THE CENTRAL COAST...POSSIBLY AS HIGH AS THE MID 70S
FOR IMMEDIATE COAST WITH SAN LUIS OBISPO REACHING AROUND 80 DEGREES.
BY TUESDAY...THE UPPER TROUGH DEEPENS CONSIDERABLY. THERE WILL BE AN
INCREASE OF LOW CLOUDS ACROSS MOST COAST AND COASTAL VALLEYS
INCLUDING THE CENTRAL COAST AND ADJACENT SANTA YNEZ VALLEY WITH HIGH
TEMPS BELOW AVG IN MOST AREAS TO AROUND NORMAL FOR THE ANTELOPE
VALLEY. THE WARMEST VALLEYS WILL REACH THE LOWER 80S WITH MOST
COASTAL AREAS IN THE 60S TO MID 70S.
BY WEDNESDAY...WITH THE TROUGH AXIS AT ITS DEEPEST PENETRATION
ACROSS SOUTHERN CAL...500 MB HEIGHTS WILL LOWER TO AROUND 575DM
ACROSS LA COUNTY WITH THICKNESS LVLS AND 950 MB TEMPS MUCH LOWER.
THIS BROAD CYCLONIC FLOW ALOFT WILL CONTINUE TO BRING AREAS OF LOW
CLOUDS AND PATCHY FOG INTO THE COASTAL SLOPES OF THE LOCAL LA/VTU
COUNTY MOUNTAINS. HIGH TEMPS WILL BE WELL BELOW AVG WITH MOST HIGHS
IN THE VALLEYS REACHING THE MID 70S WITH COASTAL AREAS REMAINING IN
THE 60S. THE ANTELOPE VALLEY SHOULD BE A GOOD 10 DEGREES BELOW AVG
WITH A HIGH OF 81 DEGREES PREDICTED. HIGHS SHOULD BOTTOM OUT ON
WEDNESDAY WITH ONLY A SLOW RECOVERY EXPECTED THROUGH THE LONG TERM
PERIOD.
***FROM PREVIOUS DISCUSSION***
.LONG TERM (THU-SUN)...THE TROF WILL MOVE EAST THU BUT ONLY A SLIGHT
WARMING TREND IS EXPECTED INTO NEXT WEEKEND AS WEAK CYCLONIC FLOW
REMAINS OVER THE AREA. AS A RESULT, I EXPECT THE MARINE LYR TO
REMAIN WELL ESTABLISHED THROUGH THE PERIOD WITH ONLY LIMITED COASTAL
CLEARING EACH DAY. HIGHS WILL REMAIN 5-10 DEGREES BELOW NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...06/0535Z.
WDSPRD STRATUS EXPECTED IN CSTL SXNS S OF PT CONCEPTION...WITH
PATCHIER CONDS ACROSS THE CENTRAL COAST. EXPECT CLOUDS TO SPREAD
INTO THE VLYS OVERNIGHT.
.KLAX...MODERATE CONFIDENCE IN TAF. XPCT HIGH IFR OR LOW MVFR CIGS
THROUGH AT LEAST 18Z. THERE IS A 20 PERCENT CHANCE CIGS COULD LINGER
AS LATE AT 21Z.
.KBUR...MODERATE CONFIDENCE IN TAF. THERE IS A 20 PERCENT CHANCE
COULD ARRIVE AS EARLY AS 07Z OR AS LATE AS 11Z.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/WOFFORD
AVIATION...DB
SYNOPSIS...MEIER
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KMTR 060518
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1018 PM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 8:45 PM PDT SUNDAY...IT WAS A BEAUTIFUL DAY
ACROSS MOST OF THE DISTRICT TODAY...EXCEPT FOR A SMALL PERSISTENT
PATCH OF STRATUS RIGHT OVER MONTEREY. TEMPS TODAY RANGED FROM THE 60S
TO LOWER 70S ALONG THE COAST...70S AND LOWER 80S AROUND THE BAY...TO
THE 80S AND LOWER 90S WELL INLAND. THE HIGH TEMPERATURE ACROSS THE
DISTRICT WAS 100 AT THE PINNACLES AND THE LOW WAS 42 AT ARROYO
SECO...CARMEL VALLEY...AND SEBASTOPOL. WITH WARMER AIR ALOFT AND A
STRONG NORTHERLY FLOW...6.8 MB BETWEEN ARCATA-SFO TEMPS ARE RUNNING
CLOSE TO FIVE DEGREES WARMER THAN YESTERDAY EVENING. WITH THE
NORTHERLY GRADIENT STRATUS HAS DISAPPEARED FROM THE COAST...EVEN
THOUGH THE FT ORD PROFILER IS INDC A WEAK AND DIFFUSE MARINE
INVERSION OF AROUND 1200 FT. THE BAY AREA SODARS ARE NOT INDC ANY
MARINE INVERSION.
OFFSHORE FLOW WILL CONTINUE OVERNIGHT AND MONDAY AS A SFC HIGH
CONTINUES TO BUILD OVER THE PACIFIC NW AND THE NORTHERN GREAT BASIN.
THERE COULD BE A PATCH OF STRATUS ALONG THE MONTEREY COUNTY COAST
THIS EVENING...PER CAMS FROM CARMEL AND NEPENTHE...BUT WITH THE
DEVELOPING OFFSHORE FLOW ANY STRATUS WILL DISSIPATE. WITH THE
OFFSHORE FLOW THE WINDS IN THE NORTH AND EAST BAY HILLS COULD BE
GUSTY AT TIMES...BUT THIS IS HANDLED IN THE FIRE WEATHER FORECAST BY
A HEADLINE...SINCE THE DURATION OF WINDS WILL BE SHORT-LIVED. LABOR
DAY WILL END OF BEING A SUNNY AND WARM DAY WITH 70S ALONG THE
IMMEDIATE COAST...80S AROUND THE BAY...AND 90S INLAND.
THE WARM SPELL WILL BE LIKE THE OTHERS THIS SUMMER...BRIEF. A TROUGH
WILL DEEPEN ALONG THE WEST COAST AND WILL SWING INLAND IN FORCE ON
WEDNESDAY. TEMPS WILL BE SIGNIFICANTLY COOLER ON WEDNESDAY WITH THE
ONSHORE FLOW...WITH 850 MB TEMPS DROPPING FROM 22C ON MONDAY TO 7C ON
WEDNESDAY. THE MARINE LAYER WILL DEEPEN SO DRIZZLE IS A POSSIBILITY.
HOWEVER...WITH 850 MB TEMPS THAT COOL IT IS POSSIBLE THAT THE MARINE
LAYER COULD MIX OUT.
CURRENT FORECAST ON TRACK...NO UPDATES.
&&
.AVIATION...AS OF 10:18 PM PDT SUNDAY...LOW PRESSURE DIVING INTO THE
GREAT BASIN COMBINED WITH A THERMAL TROUGH DEVELOPING OVER
CALIFORNIA WILL RESULT IN OFFSHORE FLOW OVERNIGHT. THE OFFSHORE
FLOW WILL PRECLUDE ANY FORMATION OF STRATUS FROM THE TERMINALS
OVER THE NEXT 24 HOURS. HOWEVER...THERE WILL BE A POSSIBILITY
OF A BRIEF PERIOD OF CIGS AT THE MONTEREY AND SALINAS TERMINALS LATE
TONIGHT AS TEMPERATURES REACH THEIR DEWPOINTS.
.VICINITY OF KSFO...VFR TONIGHT THROUGH MONDAY EVENING. LIGHT
VARIABLE WINDS WILL INCREASE OUT OF THE WEST TOMORROW AFTERNOON TO 10
TO 15 KT BY 2000Z.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...VFR WITH SOME PATCHY FOG DEVELOPING LATE
THIS EVENING. A PERIOD OF LIFR WILL BE POSSIBLE BETWEEN 1200Z AND
1600Z MONDAY MORNING. VARIABLE WINDS WILL INCREASE TO 5 TO 10 KT BY
2000Z TOMORROW.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...GLW...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: LARRY
000
FXUS66 KSTO 060425
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
925 PM PDT SUN SEP 5 2010
.DISCUSSION...WATER VAPOR IMAGERY CONTINUES TO SHOW A TROUGH OF LOW
PRESSURE DIGGING ACROSS NORTHERN NEVADA AND UTAH THIS EVENING...WITH
VERY DRY NORTHWESTERLY TO NORTHERLY FLOW ALOFT OVER NORTHERN
CALIFORNIA. IN FACT...THE AIR IS SO DRY THAT THE FOG PRODUCT SHOW
THE NEAREST CLOUDS EITHER WELL NORTH IN THE COLUMBIA RIVER
BASIN...WELL EAST NEAR THE GREAT SALT LAKE...WELL SOUTH OF 33
DEGREES NORTH...AND WELL WEST OF 127 DEGREES WEST. THE DRIER AIR
CAN ALSO BE SEEN AT THE SURFACE...AS DEW POINTS HAVE FALLEN BETWEEN
5 AND 20 DEGREES OVER THIS TIME LAST NIGHT. THIS IS THE RESULT OF
THE COLD AIR ADVECTION RELATED TO THIS SYSTEM THAT ALSO GENERATED A
GOOD NORTHERLY GRADIENT OVER NORTHERN CALIFORNIA. ALTHOUGH THE
NORTHERLY SURFACE GRADIENT IS STILL INCREASING TO AROUND 12 MBS
BETWEEN MEDFORD AND SACRAMENTO AND THE KDAX VAD ALSO SHOWS A GOOD
STEADY NORTH WIND RANGING BETWEEN 15 AND 25 KTS THROUGH THE
COLUMN...THE SURFACE WINDS APPEAR TO BE DECOUPLING IN THE VALLEY.
THEREFORE...HAVE UPDATED THE FORECAST THIS EVENING TO DECREASE THE
WINDS FOR PORTIONS OF THE VALLEY. ALSO UPDATED TEMPERATURES THIS
EVENING...PRIMARILY IN THE BURNEY BASIN AND MOUNTAIN VALLEYS...WHERE
DEW POINTS IN THESE AREAS ARE ALREADY IN THE TEENS AND TWENTIES AND
WINDS ARE RELATIVELY LIGHT AS WELL. HAVE LOWER THEIR TEMPERATURES
INTO THE MID 30S...BUT A FEW LOCATIONS MAY BRIEFLY HIT THE FREEZING
MARK. SINCE THE AIR IS SO DRY...DO NOT EXPECT FROST TO BE A
PROBLEM...BUT SENSITIVE PLANTS MAY NEED TO BE BROUGHT INSIDE OR
COVERED FOR PROTECTION.
AS FOR TOMORROW...THE NORTHERLY GRADIENT WILL STILL BE AROUND...BUT
STARTING TO WEAKEN SOME...AS A TRANSITORY RIDGE MOVES OVER THE
REGION. 850 TEMPERATURES INCREASE ABOUT A DEGREE...MAKING TOMORROW
SIMILAR TO OR SLIGHTLY WARMER THAN TODAY. THEREFORE...GET OUT AND
ENJOY THE LAST TASTE OF SUMMER ON THIS LABOR DAY. IN FACT...MONDAY
WILL BE THE LAST REAL WARM DAY ACROSS THE REGION FOR THE ABOUT THE
NEXT WEEK...AS ANOTHER UNSEASONABLY COLD TROUGH OF LOW PRESSURE DIGS
OVER THE REGION FOR TUESDAY THROUGH THURSDAY. CURRENT FORECAST
SEEMS TO BE HANDLING THESE TRENDS WELL...SO NO OTHER UPDATES ARE
PLANNED AT THIS TIME. PALMER
.AVIATION...VERY DRY NORTHWESTERLY TO NORTHERLY FLOW WILL REMAIN
OVER THE REGION THROUGH THE NEXT 12 TO 24 HOURS...WITH VFR
CONDITIONS PREVAILING. LOCALLY GUSTY NORTHEAST TO EAST WINDS UP TO
30 KTS WILL BE POSSIBLE THROUGH FAVORED CANYONS AND PASSES
TONIGHT...WHILE SOME LOCALLY GUSTY NORTH WINDS UP TO 20 KTS WILL BE
POSSIBLE IN THE VALLEY TOMORROW.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS66 KHNX 060404
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
904 PM PDT SUN SEP 5 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN AS A TROUGH OF LOW
PRESSURE BRUSHES THE REGION TODAY. THIS WILL BRING A SLIGHT COOLING
TREND THROUGH LABOR DAY. A STRONGER LOW PRESSURE SYSTEM WILL THEN
PROVIDE A MORE SIGNIFICANT COOL DOWN BY MIDWEEK AS IT PUSHES
THROUGH.
&&
.DISCUSSION...A VERY QUIET NIGHT OVER THE FORECAST AREA AS THE BIG
RIDGE GETS KNOCKED DOWN A LITTLE WITH THE PASSAGE OF A SHORT WAVE
THROUGH. TEMPERATURES COOLED SEVERAL DEGREES TODAY TO VALUES JUST
SLIGHTLY ABOVE NORMAL FOR EARLY SEPTEMBER. FOR LABOR DAY,
TEMPERATURES WILL SHOW JUST A LITTLE COOLING, BUT NOT THAT MUCH.
SHOULD BE SUNNY AND JUST SLIGHTLY WARMER THAN NORMAL. FOR TUESDAY
FORECAST MODELS LOWER HEIGHTS AROUND 30 METERS AT 500 MB AS THE
NEXT DEEPER AND COOLER PACIFIC SYSTEM APPROACHES. THIS COOL
THROUGH IS PROGGED TO MOVE THROUGH CENTRAL CALIFORNIA ON WEDNESDAY
BRINGING TEMPERATURES TO BELOW NORMAL AND A CHANCE OF SHOWERS TO
THE SIERRA. NO CHANGES TO THE CURRENT GRIDS.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 06Z TUESDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...DUDLEY
AVN/FW...DCH
SYNOPSIS...BSO
WEATHER.GOV/HANFORD
000
FXUS66 KMTR 060401
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
901 PM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 8:45 PM PDT SUNDAY...IT WAS A BEAUTIFUL DAY
ACROSS MOST OF THE DISTRICT TODAY...EXCEPT FOR A SMALL PERSISTENT
PATCH OF STRATUS RIGHT OVER MONTEREY. TEMPS TODAY RANGED FROM THE 60S
TO LOWER 70S ALONG THE COAST...70S AND LOWER 80S AROUND THE BAY...TO
THE 80S AND LOWER 90S WELL INLAND. THE HIGH TEMPERATURE ACROSS THE
DISTRICT WAS 100 AT THE PINNACLES AND THE LOW WAS 42 AT ARROYO
SECO...CARMEL VALLEY...AND SEBASTOPOL. WITH WARMER AIR ALOFT AND A
STRONG NORTHERLY FLOW...6.8 MB BETWEEN ARCATA-SFO TEMPS ARE RUNNING
CLOSE TO FIVE DEGREES WARMER THAN YESTERDAY EVENING. WITH THE
NORTHERLY GRADIENT STRATUS HAS DISAPPEARED FROM THE COAST...EVEN
THOUGH THE FT ORD PROFILER IS INDC A WEAK AND DIFFUSE MARINE
INVERSION OF AROUND 1200 FT. THE BAY AREA SODARS ARE NOT INDC ANY
MARINE INVERSION.
OFFSHORE FLOW WILL CONTINUE OVERNIGHT AND MONDAY AS A SFC HIGH
CONTINUES TO BUILD OVER THE PACIFIC NW AND THE NORTHERN GREAT BASIN.
THERE COULD BE A PATCH OF STRATUS ALONG THE MONTEREY COUNTY COAST
THIS EVENING...PER CAMS FROM CARMEL AND NEPENTHE...BUT WITH THE
DEVELOPING OFFSHORE FLOW ANY STRATUS WILL DISSIPATE. WITH THE
OFFSHORE FLOW THE WINDS IN THE NORTH AND EAST BAY HILLS COULD BE
GUSTY AT TIMES...BUT THIS IS HANDLED IN THE FIRE WEATHER FORECAST BY
A HEADLINE...SINCE THE DURATION OF WINDS WILL BE SHORT-LIVED. LABOR
DAY WILL END OF BEING A SUNNY AND WARM DAY WITH 70S ALONG THE
IMMEDIATE COAST...80S AROUND THE BAY...AND 90S INLAND.
THE WARM SPELL WILL BE LIKE THE OTHERS THIS SUMMER...BRIEF. A TROUGH
WILL DEEPEN ALONG THE WEST COAST AND WILL SWING INLAND IN FORCE ON
WEDNESDAY. TEMPS WILL BE SIGNIFICANTLY COOLER ON WEDNESDAY WITH THE
ONSHORE FLOW...WITH 850 MB TEMPS DROPPING FROM 22C ON MONDAY TO 7C ON
WEDNESDAY. THE MARINE LAYER WILL DEEPEN SO DRIZZLE IS A POSSIBILITY.
HOWEVER...WITH 850 MB TEMPS THAT COOL IT IS POSSIBLE THAT THE MARINE
LAYER COULD MIX OUT.
CURRENT FORECAST ON TRACK...NO UPDATES.
&&
.AVIATION...AS OF 4:45 PM PDT SUNDAY...LOW PRESSURE DIVING INTO THE
GREAT BASIN COMBINED WITH A THERMAL TROUGH DEVELOPING OVER
CALIFORNIA WILL RESULT IN OFFSHORE FLOW THIS EVENING. THE OFFSHORE
FLOW WILL PRECLUDE ANY FORMATION OF STRATUS FROM THE TERMINALS
OVER THE NEXT 24 HOURS. HOWEVER...THERE WILL BE A POSSIBILITY
OF A BRIEF PERIOD OF CIGS AT THE MONTEREY AND SALINAS TERMINALS LATE
TONIGHT AS THE MARINE LAYER LINGER AROUND 1200 FEET IN THIS AREA.
.VICINITY OF KSFO...VFR TONIGHT THROUGH MONDAY EVENING. WEST WINDS
20 KT GRADUALLY DIMINISHING AFTER SUNSET.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...VFR WITH SOME PATCHY FOG DEVELOPING LATE
THIS EVENING. A PERIOD OF LIFR WILL BE POSSIBLE BETWEEN 1200Z AND
1600Z MONDAY MORNING. WEST WINDS 10 TO 15 KT DIMINISHING AFTER
SUNSET.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...GLW...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: LARRY
000
FXUS65 KPSR 060336
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
836 PM MST SUN SEP 5 2010
.SYNOPSIS...
THE WEATHER PATTERN WILL CHANGE DURING THE NEXT FEW DAYS...WITH LOW
PRESSURE ALOFT BECOMING THE DOMINANT WEATHER FEATURE OVER THE
WESTERN UNITED STATES. CONSEQUENTLY...TEMPERATURES WILL TREND
DOWNWARD DURING MUCH OF THE WORK WEEK WITH BELOW NORMAL READINGS
LIKELY WEDNESDAY THROUGH FRIDAY. THE BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL OCCUR OVER SOUTH-CENTRAL ARIZONA MONDAY NIGHT
THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
QUIET WEATHER REMAINS IN PLACE THIS EVENING ACROSS THE FORECAST
AREA. ISOLATED CONVECTION DEVELOPED TO THE WEST OF NOGALES LATE THIS
AFTERNOON...BUT ONLY SOME THIN CLOUD COVER REMAINED IN ITS WAKE AS
THE STORMS DISSIPATED SEVERAL HOURS AGO. OTHERWISE SKIES ACROSS THE
PHOENIX AREA AND POINTS EAST WERE PARTLY CLOUDY/MOSTLY CLEAR.
ONLY A FEW MINOR ADJUSTMENTS TO THE FORECAST THIS EVENING...MAINLY
FOR CLOUD COVER TRENDS AND OVERNIGHT LOWS. WITH CLOUDS MOVING IN
FROM THE SOUTH...I NUDGED OVERNIGHT LOWS UP A DEGREE OR TWO FOR THE
EASTERN HALF OF THE FORECAST AREA. ALSO...DEWPOINTS HAVE BEEN SLOWLY
CREEPING UPWARD AND THIS SHOULD ALSO ACT TO KEEP TEMPS SLIGHTLY
WARMER THAN GUIDANCE VALUES. FORECAST FOR MONDAY LOOKS IN GOOD
SHAPE. A QUICK LOOK AT THE INCOMING 00Z NAM SHOWS AN INCREASE IN
MOISTURE ACROSS THE EASTERN HALF OF THE CWA /ASSOCIATED WITH A WEAK
CIRCULATION WHICH IS NOW EVIDENT SOUTHWEST OF SAN DIEGO ON THE WATER
VAPOR IMAGERY/ YET INSTABILITY REMAINS MINIMAL ACROSS THE LOWER
DESERTS. COULD SEE CONVECTION DEVELOP OUTSIDE THE CWA LATE TOMORROW
AFTERNOON WITH DISSIPATING THUNDERSTORMS/OUTFLOWS MOVING IN FROM THE
SOUTH/SOUTHEAST...OTHERWISE IT LOOKS TO BE A DRY LABOR DAY.
ADDITIONAL STORMS ARE POSSIBLE ACROSS THE REGION ON TUESDAY ALTHOUGH
INSTABILITY CONTINUES TO LOOK QUESTIONABLE AT BEST. I WILL PASS
THESE CONCERNS ALONG TO THE INCOMING SHIFT.
NAM AND GFS DIFFER ON THE QPF WITH THE GFS BEING MORE GENEROUS.
NEITHER MODEL HAS MUCH IN THE WAY OF QG FORCING OR INSTABILITY SO
THE MORE MODEST NAM QPF MAKES MORE SENSE. IT IS INDICATING
SUBSTANTIAL CONVECTIVE ACTIVITY OVER PIMA AND SANTA CRUZ COUNTIES
MONDAY WITH REMNANT/DEBRIS SHOWERS DRIFTING NORTHWARD MONDAY NIGHT.
IT REDEVELOPS CONVECTION TUESDAY AFTERNOON AS DAYTIME
DESTABILIZATION OCCURS AND THE LARGE TROUGH IN THE WESTERLIES SAGS
SOUTHWARD. THE GFS SEEMS TO PEAK THE QPF LATE MONDAY NIGHT AND
DECREASE IT DURING THE DAY...WITHOUT MUCH IN THE WAY OF
REDEVELOPMENT. THIS SCENARIO SEEMS LESS SOUND...ESPECIALLY SINCE ITS
FORECAST SOUNDINGS ARE MORE UNSTABLE TUESDAY AFTERNOON THAN MONDAY
NIGHT AND THERE ARENT ANY DEEP SATURATED LAYERS BEING DEPICTED.
MEANWHILE TEMPERATURES WILL BE ON THE DECLINE. THE LARGE TROUGH IN
THE WESTERLIES DEEPENS WEDNESDAY FOR ADDITIONAL COOLING IN OUR
WESTERN AREAS...THOUGH THE TROUGH AXIS IS STILL TO OUR WEST...FOR
MAX TEMPS ON THE LOWER DESERTS CLOSE TO 100. MUCH DRIER AIR WILL
BEGIN TO PUSH INTO ARIZONA ON WEDNESDAY AS WELL.
IN THE EXTENDED...THE TROUGH MOVES ACROSS THE INTERMOUNTAIN WEST AND
ROCKIES THURSDAY AND FRIDAY FOR A BIT OF ADDITIONAL COOLING WITH
HIGHS ON THE LOWER DESERTS IN THE MID AND UPPER 90S. DRY AIR WILL
OVERSPREAD THE ENTIRE SOUTHWESTERN U.S. AS WELL. TEMPS WILL BEGIN TO
INCREASE NEXT WEEKEND AS THE RIDGE CENTERED OVER THE
SOUTH-CENTRAL UNITED STATES STRENGTHENS AND EXPANDS TOWARD THE
WEST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
ONLY A FEW HIGH CLOUDS AT BOTH KPHX/KIWA THROUGH THE OVERNIGHT
HOURS...GRADUALLY GIVING WAY TO MOSTLY CLEAR SKIES AROUND DAYBREAK.
SOME HIGH CLOUDS WILL RETURN LATE IN THE FORECAST PERIOD MONDAY
AFTERNOON/EVENING AS CONVECTION DEVELOPS TO THE SOUTH. WHILE I WILL
NOT INCLUDE IT IN THE TAF...DISSIPATING THUNDERSTORMS WELL SOUTH OF
THE PHOENIX AREA COULD BRING SOME BLOWING DUST INTO KIWA AND MAYBE
KPHX AFTER 00Z BUT CONFIDENCE IN EXACT TIMING/PROBABILITY TOO LOW AT
THIS POINT.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKIES EXPECTED AT BOTH SITES THROUGH THE FORECAST PERIOD.
WINDS WILL GRADUALLY DIMINISH OVERNIGHT WITH ANOTHER ROUND OF LATE
AFTERNOON BREEZINESS LIKELY MONDAY AFTERNOON.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS EAST OF GLOBE
WEDNESDAY. OTHERWISE...LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS
EXPECTED TO DEVELOP NEAR THE WEST COAST WITH COOLER WEATHER
WEDNESDAY. THIS SYSTEM IS ALSO EXPECTED TO RESULT IN BREEZY WEATHER
FROM THE SOUTHWEST WEDNESDAY AFTERNOON WITH GUSTS BETWEEN 20 AND 30
MPH. SOMEWHAT BELOW AVERAGE TEMPERATURES FOR EARLY SEPTEMBER AND DRY
AIR ARE EXPECTED THROUGH THE PERIOD WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/AJ
AVIATION...LEINS
FIRE WEATHER...ELLIS
000
FXUS66 KSGX 060331
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 PM PDT SUN SEP 5 2010
.SYNOPSIS...UPPER LEVEL LOW PRESSURE MOVING PAST TO THE NORTH WILL
BRING A COOLING TREND AND A DEEPER MARINE LAYER THROUGH MID WEEK.
LOW CLOUDS AND FOG WILL BECOME MORE EXTENSIVE DURING THE NIGHTS AND
MORNINGS WEST OF THE MOUNTAINS. LOCALLY WINDY AT TIMES IN THE
MOUNTAINS AND DESERTS. A LITTLE WARMER TOWARD THE END OF THE WEEK
WITH WEAKER LOW PRESSURE ALOFT.
&&
.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
.SHORT TERM (TONIGHT-WEDNESDAY)...SKIES WERE CLEAR THIS EVENING
EXCEPT FOR AREAS OF STRATUS NEAR THE COAST MOVING ONSHORE. THE 00Z
NKX SOUNDING HAD AN INVERSION BASED NEAR 1600 FT...ABOUT 600 FT
HIGHER THAN 24 HOURS PREVIOUS. INCREASING ONSHORE GRADIENTS WITH
ABOUT 8 MB SAN-IPL.
AN UPPER TROUGH WILL DEEPEN OVER THE WESTERN STATES THROUGH
WEDNESDAY. THIS WILL BRING A COOLING TREND AND A DEEPER MARINE
LAYER. MAX TEMPS WILL BE A LITTLE BELOW SEASONAL AVERAGE W OF THE
MOUNTAINS MONDAY AND WELL BELOW BY WEDNESDAY. HIGH TEMPERATURES WILL
BE ABOUT 8 TO 16 DEGREES BELOW AVERAGE IN MOST AREAS WEDNESDAY.
THERE COULD BE SOME NEAR RECORD LOW MAXIMUM TEMPERATURES WEDNESDAY.
THE MARINE LAYER WILL DEEPEN WITH LOW CLOUDS AND FOG BECOMING MORE
EXTENSIVE W OF THE MOUNTAINS EACH NIGHT. STRATUS WILL GET INTO MOST
INLAND VALLEYS AREAS TUESDAY NIGHT. ONLY PARTIAL AFTERNOON CLEARING
IN THE COASTAL AREAS TUESDAY AND WEDNESDAY. THERE ARE ALSO SOME
INDICATIONS OF A LITTLE MID LEVEL MOISTURE TUESDAY THAT COULD CAUSE
A FEW AFTERNOON CLOUDS OVER THE MOUNTAINS. STRONGER ONSHORE FLOW
AND WINDS ALOFT WILL CAUSE LOCAL GUSTY WINDS IN THE MOUNTAINS AND
DESERTS...MAINLY DURING THE AFTERNOONS AND EVENINGS TUESDAY AND
WEDNESDAY.
&&
.LONG TERM (THURSDAY-SUNDAY)...CONTINUED COOL THURSDAY. MARINE LAYER
CLOUDS WILL GET INTO THE LOWER COASTAL MOUNTAIN SLOPES THURSDAY
MORNING WITH PARTIAL AFTERNOON CLEARING. GRADUALLY WARMER WITH A
SHALLOWER MARINE LAYER FRIDAY THROUGH THE WEEKEND AS LOCAL HEIGHTS
RECOVER UNDER WEAKER CYCLONIC FLOW ALOFT. EVEN WITH THE
WARMING...MAX TEMPS WILL STILL BE LOWER THAN SEASONAL AVERAGES.
&&
.AVIATION...
060315Z...MARINE STRATUS LAYER BETWEEN 1K AND 1.5K FT OVER COASTAL
AREAS EARLY THIS EVENING IS EXPECTED TO DEEPEN WITH BASES NEAR 1.5K
FT AND TOPS AROUND FL020 BY MORNING AND PENETRATE 15 TO 20 MILES
INLAND WITH AREAS OF 3-5SM VIS IN BR/HZ...AND LOCAL LIFR CIGS/VIS
FAR INLAND AND OVER HIGHER COASTAL TERRAIN THROUGH 15Z MON. THERE IS
A POTENTIAL FOR IFR CIGS/VIS TO REACH KONT BY MORNING. WILL DROP VIS
THERE BY SUN-UP BUT NOT CONFIDENT ENOUGH TO BRING IN CIGS ATTM.
WIDESPREAD STRATUS/VIS RESTRICTIONS AROUND SUN-UP WEST OF THE MTNS
SHOULD BURN BACK TO THE COAST BETWEEN 16Z AND 19Z MON. ELSEWHERE VFR
CONDITIONS SHOULD PREVAIL UNDER A CLEAR SKY WITH VIS UNRESTRICTED.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...ATKIN
AVIATION...JAD
000
FXUS66 KLOX 060251
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
755 PM PDT SUN SEP 5 2010
...UPDATED AVIATION DISCUSSION...
.SYNOPSIS...
TEMPERATURES WILL CONTINUE TO DROP THROUGH WEDNESDAY AS ANOTHER
SERIES OF UPPER LEVEL LOW PRESSURE SYSTEMS MOVE THROUGH THE WEST
COAST. NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL EXPAND INTO THE
VALLEYS TONIGHT...AND WILL POSSIBLY REACH THE COASTAL SLOPES BY MID
WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-WED)...FIRST OF ALL...WE APOLOGIZE FOR ANY
INCONVENIENCE FOR THE DELAY IN RECEIVING PRODUCTS THIS AFTERNOON.
THERE WAS A COMMS ISSUE THAT WAS SOLVED LATE THIS AFTERNOON.
TEMPERATURES WERE DOWN SIGNIFICANTLY AS EXPECTED TODAY WITH MOST
INLAND AREAS LOWER 7 TO 10 DEGREES...WHILE THE COASTAL AREAS WERE
DOWN 3 TO 5 DEGREES FOR THE MOST PART.
THE UPPER LVL RIDGE WILL CONTINUE TO BREAKDOWN OVERNIGHT AS A BROAD
TROUGH BEGINS TO PUSH SOUTH FROM THE PAC NW. THERE WILL BE AN
OVERALL COOLING TREND ON MONDAY...ESPECIALLY FOR AREAS S OF POINT
CONCEPTION WHERE A CATALINA EDDY SHOULD DEVELOP. THE COMBINATION OF
THIS EDDY BRINGING A DEEPER MARINE LAYER OVERNIGHT AND STRONGER
ONSHORE GRADIENTS FOR LAX-DAG AND LAX-BFL SHOULD TRANSLATE INTO AN
ADDITIONAL 5 TO 10 DEGREES OF COOLING WITH LA/VTU COUNTY HIGHS ONLY
REACHING THE UPPER 70S TO MID 80S. LATEST AMDAR SOUNDING NEAR KLAX
INDICATED THE MARINE LAYER AROUND 1000 FT DEEP THIS EVENING. THE
EDDY SHOULD HELP TO DEEPEN AND WEAKEN THE INVERSION A BIT. THIS
SHOULD ALLOW SOME PATCHY LOW CLOUDS AND FOG TO CREEP INTO THE
COASTAL VALLEYS OVERNIGHT. AREAS N OF POINT CONCEPTION COULD SEE
SOME PATCHY LOW CLOUDS DEVELOP NEAR LOMPOC TO SANTA MARIA...AND
POSSIBLY SANTA YNEZ OVERNIGHT...HOWEVER 950MB-850MB WIND FLOW FROM
THE NAM-WRF WILL BE OUT OF THE EAST TOMORROW MORNING...LIKELY DUE TO
PASSING COLD FRONT ACROSS NEVADA. THIS SHOULD BRING A FEW DEGREES OF
WARMING ACROSS THE CENTRAL COAST...POSSIBLY AS HIGH AS THE MID 70S
FOR IMMEDIATE COAST WITH SAN LUIS OBISPO REACHING AROUND 80 DEGREES.
BY TUESDAY...THE UPPER TROUGH DEEPENS CONSIDERABLY. THERE WILL BE AN
INCREASE OF LOW CLOUDS ACROSS MOST COAST AND COASTAL VALLEYS
INCLUDING THE CENTRAL COAST AND ADJACENT SANTA YNEZ VALLEY WITH HIGH
TEMPS BELOW AVG IN MOST AREAS TO AROUND NORMAL FOR THE ANTELOPE
VALLEY. THE WARMEST VALLEYS WILL REACH THE LOWER 80S WITH MOST
COASTAL AREAS IN THE 60S TO MID 70S.
BY WEDNESDAY...WITH THE TROUGH AXIS AT ITS DEEPEST PENETRATION
ACROSS SOUTHERN CAL...500 MB HEIGHTS WILL LOWER TO AROUND 575DM
ACROSS LA COUNTY WITH THICKNESS LVLS AND 950 MB TEMPS MUCH LOWER.
THIS BROAD CYCLONIC FLOW ALOFT WILL CONTINUE TO BRING AREAS OF LOW
CLOUDS AND PATCHY FOG INTO THE COASTAL SLOPES OF THE LOCAL LA/VTU
COUNTY MOUNTAINS. HIGH TEMPS WILL BE WELL BELOW AVG WITH MOST HIGHS
IN THE VALLEYS REACHING THE MID 70S WITH COASTAL AREAS REMAINING IN
THE 60S. THE ANTELOPE VALLEY SHOULD BE A GOOD 10 DEGREES BELOW AVG
WITH A HIGH OF 81 DEGREES PREDICTED. HIGHS SHOULD BOTTOM OUT ON
WEDNESDAY WITH ONLY A SLOW RECOVERY EXPECTED THROUGH THE LONG TERM
PERIOD.
***FROM PREVIOUS DISCUSSION***
.LONG TERM (THU-SUN)...THE TROF WILL MOVE EAST THU BUT ONLY A SLIGHT
WARMING TREND IS EXPECTED INTO NEXT WEEKEND AS WEAK CYCLONIC FLOW
REMAINS OVER THE AREA. AS A RESULT, I EXPECT THE MARINE LYR TO
REMAIN WELL ESTABLISHED THROUGH THE PERIOD WITH ONLY LIMITED COASTAL
CLEARING EACH DAY. HIGHS WILL REMAIN 5-10 DEGREES BELOW NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...06/0200Z.
MODERATE CONFIDENCE WITH 00Z TAF PACKAGE IN REGARDS TO TIMING OF
STRATUS RETURNING TO COAST AND KBUR...KVNY.
MARINE LAYER SHOULD DEEPEN OVERNIGHT TO AROUND 1200 FT. THIS SHOULD
ALLOW SOME PATCHY IFR CIGS TO DEVELOP AROUND KBUR AND KVNY AFTER
MIDNIGHT.
40 PERCENT CHANCE FOR IFR/LIFR CIGS TO RETURN TO KSMX BEFORE 06Z.
30 PERCENT CHANCE FOR IFR.LIFR CIGS TO RETURN TO KSBA BEFORE 09Z.
40 PERCENT CHANCE FOR IFR CIGS TO RETURN TO KBUR AND KVNY BEFORE 10Z.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/WOFFORD
AVIATION...KAPLAN
SYNOPSIS...MEIER
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KLOX 060244
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
745 PM PDT SUN SEP 5 2010
.SYNOPSIS...
TEMPERATURES WILL CONTINUE TO DROP THROUGH WEDNESDAY AS ANOTHER
SERIES OF UPPER LEVEL LOW PRESSURE SYSTEMS MOVE THROUGH THE WEST
COAST. NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL EXPAND INTO THE
VALLEYS TONIGHT...AND WILL POSSIBLY REACH THE COASTAL SLOPES BY MID
WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-WED)...FIRST OF ALL...WE APOLOGIZE FOR ANY
INCONVENIENCE FOR THE DELAY IN RECEIVING PRODUCTS THIS AFTERNOON.
THERE WAS A COMMS ISSUE THAT WAS SOLVED LATE THIS AFTERNOON.
TEMPERATURES WERE DOWN SIGNIFICANTLY AS EXPECTED TODAY WITH MOST
INLAND AREAS LOWER 7 TO 10 DEGREES...WHILE THE COASTAL AREAS WERE
DOWN 3 TO 5 DEGREES FOR THE MOST PART.
THE UPPER LVL RIDGE WILL CONTINUE TO BREAKDOWN OVERNIGHT AS A BROAD
TROUGH BEGINS TO PUSH SOUTH FROM THE PAC NW. THERE WILL BE AN
OVERALL COOLING TREND ON MONDAY...ESPECIALLY FOR AREAS S OF POINT
CONCEPTION WHERE A CATALINA EDDY SHOULD DEVELOP. THE COMBINATION OF
THIS EDDY BRINGING A DEEPER MARINE LAYER OVERNIGHT AND STRONGER
ONSHORE GRADIENTS FOR LAX-DAG AND LAX-BFL SHOULD TRANSLATE INTO AN
ADDITIONAL 5 TO 10 DEGREES OF COOLING WITH LA/VTU COUNTY HIGHS ONLY
REACHING THE UPPER 70S TO MID 80S. LATEST AMDAR SOUNDING NEAR KLAX
INDICATED THE MARINE LAYER AROUND 1000 FT DEEP THIS EVENING. THE
EDDY SHOULD HELP TO DEEPEN AND WEAKEN THE INVERSION A BIT. THIS
SHOULD ALLOW SOME PATCHY LOW CLOUDS AND FOG TO CREEP INTO THE
COASTAL VALLEYS OVERNIGHT. AREAS N OF POINT CONCEPTION COULD SEE
SOME PATCHY LOW CLOUDS DEVELOP NEAR LOMPOC TO SANTA MARIA...AND
POSSIBLY SANTA YNEZ OVERNIGHT...HOWEVER 950MB-850MB WIND FLOW FROM
THE NAM-WRF WILL BE OUT OF THE EAST TOMORROW MORNING...LIKELY DUE TO
PASSING COLD FRONT ACROSS NEVADA. THIS SHOULD BRING A FEW DEGREES OF
WARMING ACROSS THE CENTRAL COAST...POSSIBLY AS HIGH AS THE MID 70S
FOR IMMEDIATE COAST WITH SAN LUIS OBISPO REACHING AROUND 80 DEGREES.
BY TUESDAY...THE UPPER TROUGH DEEPENS CONSIDERABLY. THERE WILL BE AN
INCREASE OF LOW CLOUDS ACROSS MOST COAST AND COASTAL VALLEYS
INCLUDING THE CENTRAL COAST AND ADJACENT SANTA YNEZ VALLEY WITH HIGH
TEMPS BELOW AVG IN MOST AREAS TO AROUND NORMAL FOR THE ANTELOPE
VALLEY. THE WARMEST VALLEYS WILL REACH THE LOWER 80S WITH MOST
COASTAL AREAS IN THE 60S TO MID 70S.
BY WEDNESDAY...WITH THE TROUGH AXIS AT ITS DEEPEST PENETRATION
ACROSS SOUTHERN CAL...500 MB HEIGHTS WILL LOWER TO AROUND 575DM
ACROSS LA COUNTY WITH THICKNESS LVLS AND 950 MB TEMPS MUCH LOWER.
THIS BROAD CYCLONIC FLOW ALOFT WILL CONTINUE TO BRING AREAS OF LOW
CLOUDS AND PATCHY FOG INTO THE COASTAL SLOPES OF THE LOCAL LA/VTU
COUNTY MOUNTAINS. HIGH TEMPS WILL BE WELL BELOW AVG WITH MOST HIGHS
IN THE VALLEYS REACHING THE MID 70S WITH COASTAL AREAS REMAINING IN
THE 60S. THE ANTELOPE VALLEY SHOULD BE A GOOD 10 DEGREES BELOW AVG
WITH A HIGH OF 81 DEGREES PREDICTED. HIGHS SHOULD BOTTOM OUT ON
WEDNESDAY WITH ONLY A SLOW RECOVERY EXPECTED THROUGH THE LONG TERM
PERIOD.
***FROM PREVIOUS DISCUSSION***
.LONG TERM (THU-SUN)...THE TROF WILL MOVE EAST THU BUT ONLY A SLIGHT
WARMING TREND IS EXPECTED INTO NEXT WEEKEND AS WEAK CYCLONIC FLOW
REMAINS OVER THE AREA. AS A RESULT, I EXPECT THE MARINE LYR TO
REMAIN WELL ESTABLISHED THROUGH THE PERIOD WITH ONLY LIMITED COASTAL
CLEARING EACH DAY. HIGHS WILL REMAIN 5-10 DEGREES BELOW NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...06/0200Z. WILL BE UPDATED SHORTLY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/WOFFORD
AVIATION...30
SYNOPSIS...MEIER
WWW.WEATHER.GOV/LOSANGELES
000
FXUS65 KREV 060138 AAA
AFDREV
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE RENO NV
638 PM PDT SUN SEP 5 2010
.UPDATE...
VISIBLE SATELLITE IMAGERY AND KNFL OBSERVATION INDICATE DUST HAS
BEEN PICKED UP BY THE NORTHEAST WINDS. KNFL DOWN TO 1 1/2 MILES
AND PLUME CONTINUES TO FEED OFF THE CARSON SINK. WILL UPDATE TO
ADD DUST TO ZONES 1 AND 4...AND ALSO ISSUE SPS FOR REDUCED
VISIBILITY ON HIGHWAYS 50 AND 95 IN WESTERN NEVADA. WALLMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 315 PM PDT SUN SEP 5 2010/
SHORT TERM...
AN UPPER LOW IS SWIFTLY MOVING THROUGH IDAHO AND WESTERN MONTANA
THIS AFTERNOON. THE MAIN COLD AIR ADVECTION ASSOCIATED WITH THE
LOW WILL BE OVER CENTRAL AND EASTERN NEVADA WITH THE MAIN SURFACE
HIGH SETTLING ACROSS FAR NORTHEASTERN NEVADA BY EARLY MONDAY MORNING.
HOWEVER...MODEST HIGH PRESSURE WILL BACKDOOR INTO WESTERN NEVADA
AND NORTHEAST CALIFORNIA TONIGHT WITH THE NAM SHOWING -8 MB OF
SURFACE GRADIENT FROM SACRAMENTO TO RENO BY 12Z/5 AM MONDAY. AS THE
COLD AIR ADVECTION IS MODEST OVER THE SIERRA...THE EASTERLY WIND
EVENT ON LAKE TAHOE MAY BE SHORTER-LIVED THAN PREVIOUSLY THOUGHT
WITH THE BEST CHANCE FOR STRONG NE-E WINDS NOW LOOKING LIKE FROM
LATE EVENING UNTIL AROUND 5 AM MONDAY. HOWEVER...I WILL LEAVE THE
LAKE WIND ADVISORY UNTIL 10 AM MONDAY WITH SOME UNCERTAINTY AS TO
WHEN THE HIGHER WIND CHANCES WILL DIMINISH (AND WITH IT BEING A
HIGH IMPACT PERIOD FOR LAKE TAHOE ACTIVITIES).
MONDAY...ANY SIGNIFICANT EASTERLY WINDS SHOULD DECREASE BY EARLY-
MID MORNING WITH LIGHT FLOW IN THE AFTERNOON. WITH DRY AIR AND
LIGHT WINDS...TEMPERATURES MONDAY MORNING WILL BOTTOM OUT IN THE
UPPER 20S TO LOWER 30S FOR THE SIERRA VALLEY (NORTH OF TRUCKEE)
AND OVER TO AROUND PORTOLA. BY AFTERNOON...A VERY NICE LABOR DAY
IS ON TAP WITH HIGHS REBOUNDING INTO THE 70S UNDER SUNNY SKIES FOR
MOST VALLEYS.
TUESDAY...WINDS PICK UP AGAIN BY AFTERNOON AS ANOTHER UPPER LOW
APPROACHES THE REGION. THE INCREASED WINDS/MIXING WILL BRING A
REBOUND OF 5 TO 10 DEGREES FOR MOST LOCATIONS OUTSIDE OF THE SIERRA.
TUESDAY NIGHT LOOKS MUCH MILDER LOWS FOR THE VALLEYS AS INCREASED
MOISTURE AND GUSTY RIDGE WINDS HOLD DOWN DECOUPLING.
WEDNESDAY...THE UPPER LOW WILL SWING THROUGH THE REGION DRAGGING A
COLD FRONT THROUGH THE ENTIRE CWA WEDNESDAY NIGHT. HIGHS WEDNESDAY
WILL BE BELOW AVERAGE AS COLDER AIR ALOFT FILTERS INTO THE REGION.
PRECIP WISE...THE FOCUS WILL BE ACROSS THE NORTHERN AND NORTHWESTERN
CWA LATE TUESDAY NIGHT AND WEDNESDAY WITH THE COLD FRONT FOCUSING
PRECIP THERE. ELSEWHERE...IT LOOKS LIKE MAINLY A WIND SITUATION
WITH THE PRE-FRONTAL AIRMASS SHOWING ONLY SHALLOW MOISTURE WHICH
WILL TEND TO KEEP SHOWERS CONFINED TO NEAR THE SIERRA AND ACROSS
FAR NORTHWEST NEVADA NEAR THE LOW LEVEL COLD FRONT.
AS THE FRONT DRIVES SOUTH AND EAST WITH THE CORE OF THE UPPER LOW
WEDNESDAY NIGHT...AREAS FURTHER SOUTH WILL HAVE A CHANCE OF PRECIP
AS THE ATMOSPHERE MOISTENS UP WITH INCREASED UPPER FORCING.
SNYDER
LONG TERM...THURSDAY THROUGH SUNDAY...
LITTLE CHANGE TO THE GOING FORECAST WITH UNSETTLED WEATHER ON
THURSDAY. FRIDAY INTO THE WEEKEND WILL BE FALL LIKE WITH MILD
CONDITIONS AND MODERATING TEMPERATURES...ALTHOUGH THEY WILL STAY
BELOW NORMAL FOR THE PERIOD.
ELONGATED UPPER TROUGH WILL EXTEND FROM THE PACNW INTO NW NEVADA
SOUTH TO THE TAHOE BASIN EARLY THURSDAY...LIFTING OFF TO THE
NORTHEAST THURSDAY EVENING. THE OPERATIONAL EC AND GFS RUNS HAD COME
CLOSER IN LINE BUT THE LATEST OPERATIONAL GFS IS NOW A GOOD 12 HOURS
FASTER WITH THE TROUGH. WILL CONTINUE TO LEAN TOWARD THE SLOWER EC
AS THE TROUGH IS RELATIVELY DEEP AND COLD WHICH INTUITIVELY WOULD
POINT TO THE SLOWER SOLUTION. THE TROUGH IS NOT INDICATED TO BE
QUITE AS COLD WITH 700MB TEMPERATURES DOWN TO -2C. SHOWERS WILL BE
MOST NUMEROUS NORTH OF INTERSTATE 80 ALTHOUGH A LITTLE LIGHT SNOW
MIGHT BE POSSIBLE FOR THE HIGHEST PEAKS AROUND THE TAHOE BASIN. ALSO
EXPECT BREEZY WEST-NORTHWEST WINDS IN THE WAKE OF THE TROUGH
THURSDAY AFTERNOON AND EVENING.
FOR FRIDAY THROUGH THE WEEKEND THE UPPER FLOW WILL BE GENERALLY
ZONAL WITH GRADUALLY INCREASING HEIGHTS. BY SUNDAY MEDIUM RANGE
MODELS DIVERGE SOMEWHAT ALTHOUGH THE TREND IS TO DEVELOP A TROUGH
ALONG THE WEST COAST WITH WEST TO SOUTHWEST FLOW ALOFT. WILL
CONTINUE DRY FORECAST FOR THIS PERIOD WITH TEMPERATURES SLOWLY
MODERATING TO JUST BELOW NORMAL BY SUNDAY. JAH
AVIATION...
VFR AT TAF SITES. FRONT PUSHED THROUGH KRNO AREA THIS MORNING
RESULTING IN NORTH AFTERNOON WINDS. WINDS WILL CONTINUE TO VEER TO
AN EASTERLY DIRECTION TONIGHT WITH EAST WINDS AGAIN MONDAY. JAH
FIRE WEATHER...
WILL ISSUE A FIRE WEATHER WATCH FOR TUESDAY AFTERNOON INTO EARLY
EVENING IN PARTS OF WRN NV AND NERN CA AS INDICATED IN THE
WATCH/WARNING SEGMENT BELOW. TIGHTENING GRADIENT AHEAD OF NEXT TROF
WILL LEAD TO INCREASED WINDS BY TUES AFTN ACROSS THE REGION.
CONFIDENCE IS HIGHEST FOR ZONE 450 TO MEET BOTH RH AND WIND CRITERIA
FOR THE NECESSARY DURATION. ZONE 453 WILL CERTAINLY BE DRY ENOUGH
WITH A BIT MORE UNCERTAINTY ON DURATION AND MAGNITUDE OF STRONGER
WIND GUSTS...WHILE FOR 458/278 THE SOUTHERN HALF OF EACH ZONE HAS
BEST POTENTIAL FOR REACHING BOTH WIND AND RH CRITERIA. WITH GUIDANCE
INDICATING A RAPID RISE IN HUMIDITY TUESDAY EVENING THIS EVENT
SHOULD BE SHORTER LIVED...BUT A 3-6 HOUR WINDOW OF OPPORTUNITY
EXISTS FOR CRITICAL FIRE WEATHER CONDITIONS IN THE WATCH AREA.
FARTHER SOUTH...MORE UNCERTAINTY EXISTS TO WHETHER WINDS WILL
INCREASE SUFFICIENTLY BY TUES AFTN...ALTHOUGH POTENTIAL FOR STRONGER
WINDS EXISTS TUES NIGHT WITH HUMIDITY ALSO RISING. MEANWHILE FROM
TAHOE NORTHWARD ACROSS WRN LASSEN COUNTY AND SURPRISE VALLEY...THE
HUMIDITY IS LESS LIKELY TO REMAIN LOW ENOUGH FOR ENOUGH TIME BY THE
TIME THE WINDS KICK IN AND ADVECT MORE MOISTURE. THEREFORE THESE
AREAS WERE LEFT OUT OF THE WATCH AT THIS TIME. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING NVZ450-453-458.
LAKE WIND ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT MONDAY
FOR LAKE TAHOE IN NVZ002.
CA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING CAZ278.
LAKE WIND ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT MONDAY
FOR LAKE TAHOE IN CAZ072.
&&
$$
HTTP://WEATHER.GOV/RENO
000
FXUS66 KLOX 052358
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
220 PM PDT SUN SEP 5 2010
.SYNOPSIS...
TEMPERATURES WILL CONTINUE TO DROP THROUGH WEDNESDAY AS ANOTHER
SERIES OF UPPER LEVEL LOW PRESSURE SYSTEMS MOVE THROUGH THE WEST
COAST. NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL EXPAND INTO THE
VALLEYS TONIGHT...AND WILL POSSIBLY REACH THE COASTAL SLOPES BY MID
WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-WED)...COOLING TREND BEGAN TODAY WITH MOST INLAND
AREA HIGHS DOWN 10-15 DEGREES. MARINE INVERSION STILL VERY SHALLOW
AND SATELLITE SHOWS CLOUDS ERODING RAPIDLY FROM THE WEST. TOUGH TO
SAY WHETHER THIS CLEARING TREND WILL REACH THE LA COUNTY COAST BY
EVENING, BUT EITHER WAY WE SHOULD SEE LOW CLOUDS MONDAY MORNING
ALONG THE COAST UP TO AT LEAST VENTURA COUNTY AND POSSIBLY MOVING
INTO THE LOWER COASTAL VALLEYS. INCREASING NW WINDS AROUND PT
CONCEPTION OVER THE LAST 12 HOURS OR SO IS EXPECTED TO SPIN UP AN
EDDY CIRCULATION TONIGHT AND MONDAY WHICH WILL DEEPEN THE MARINE LYR
AND LIFT IT HIGH ENOUGH TO NUDGE INTO THE LOWER VALLEY AREAS. ONLY
PATCHY LOW CLOUDS AT BEST EXPECTED ALONG THE CENTRAL COAST AND SRN
SBA COUNTY.
INTERESTING SCENARIO SETTING UP FOR MONDAY. THE EDDY CIRCULATION
WILL LIKELY BEING FURTHER COOLING TO MOST OF LA/VENTURA COUNTIES.
HOWEVER, WITH THE TROF PASSING INLAND THROUGH THE PAC NW, A WEAK
NORTHEAST FLOW SETS UP ABOVE 950 MB AND MAY ACTUALLY BRING A LITTLE
WARMING TO THE CENTRAL COAST. WITH THE EDDY DEVELOPING DOWN SOUTH
IT`S UNLIKELY THIS NORTHEAST FLOW WILL HAVE MUCH IMPACT THERE,
HOWEVER IT WILL PROBABLY RESULT IN WEAKER ONSHORE BREEZES IN THE
ANTELOPE VALLEY.
THE REMAINDER OF THE FORECAST IS PRETTY MUCH AS IT WAS. A DEEPER
TROF WILL DEVELOP ALONG THE COAST LATE TUE INTO WED. THIS WILL BRING
MORE COOLING TO THE AREA AND FURTHER DEEPENING OF THE MARINE LYR. I
ALSO EXPECT THE LOW CLOUDS TO SURGE NORTHWARD BY TUESDAY AND BRING
COOLING TO THE CENTRAL COAST. HIGHS WILL LIKELY BOTTOM OUT
WEDNESDAY, TOPPING OUT ONLY IN THE 70S IN THE VALLEYS.
.LONG TERM (THU-SUN)...THE TROF WILL MOVE EAST THU BUT ONLY A SLIGHT
WARMING TREND IS EXPECTED INTO NEXT WEEKEND AS WEAK CYCLONIC FLOW
REMAINS OVER THE AREA. AS A RESULT, I EXPECT THE MARINE LYR TO
REMAIN WELL ESTABLISHED THROUGH THE PERIOD WITH ONLY LIMITED COASTAL
CLEARING EACH DAY. HIGHS WILL REMAIN 5-10 DEGREES BELOW NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...05/1800Z.
A MID/UPPER LEVEL TROUGH OF LOW PRESSURE NORTH AND A WEAK TROUGH
SOUTH OF THE AREA WILL SHIFT EAST AS HIGH PRESSURE OVER THE AREA
WEAKENS. MODERATE UPPER LEVEL SOUTHWEST WINDS WILL BECOME MODERATE
WEST BY 06/12Z WHILE LIGHT MID LEVEL NORTH WINDS BECOME LIGHT EAST
NORTHEAST AFTER 06/15Z. WEAK PRESSURE GRADIENT WILL BECOME WEAK
ONSHORE 05/21-06/03Z AND AFTER 06/19Z. MARINE LAYER WAS AROUND .7KFT
THIS MORNING WILL ASCEND AND DIFFER BY APPROXIMATELY 1KFT MONDAY
MORNING.
KLAX...IT IS LIKELY LOW LEVEL CIGS WILL RETURN TONIGHT. THERE IS
A CHANCE CURRENT CONDITIONS WILL PERSIST THROUGH 06/09Z WITH CIGS AT
007 DEVELOPING AND DESCENDING TO 003 WITH VSBY 1/2SM FG BY 06/11Z.
IT IS LIKELY CIGS/VSBY WILL ASCEND AFTER 06/16Z AND BECOME SCATTERED
AFTER 06/18Z.
KBUR...IT IS LIKELY LOW LEVEL CIGS WILL DEVELOP TONIGHT AND A CHANCE
AT 009 BY 06/12Z.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...WOFFORD
AVIATION...30
SYNOPSIS...MEIER
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KMTR 052346
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
445 PM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 2:15 PM PDT SUNDAY...AN OFFSHORE FLOW WILL
DEVELOP TONIGHT PRODUCING GUSTY NORTH TO NORTHEAST WINDS OVER THE
HIGHER TERRAIN. A WARM AIRMASS WILL ACCOMPANY THE OFFSHORE FLOW
PROVIDING A WARM LABOR DAY. ALSO...THE SKY WILL REMAIN CLEAR...
EXCEPT IN AND AROUND THE MONTEREY BAY TONIGHT AND MONDAY MORNING.
TEMPERATURES AT 850MB ARE AROUND 22 DEGREES CELSIUS WHICH WILL
PROMOTE AFTERNOON HIGHS ON LABOR DAY IN THE 70S NEAR THE COAST...80S
AROUND THE SAN FRANCISCO BAY...90S INLAND VALLEYS AND EVEN UP TO 105
IN THE INTERIOR VALLEYS OF MONTEREY AND SAN BENITO COUNTIES. THE
WARMTH WILL BE SHORT LIVED HOWEVER AS A TROUGH MOVES QUICKLY TOWARD
CALIFORNIA. 850MB TEMPERATURES DROP FROM 22 DEGREES MONDAY
AFTERNOON TO 15 DEGREES TUESDAY AFTERNOON AS THE TROUGH APPROACHES.
THEN THE 850MB TEMPERATURE DROPS TO 10 DEGREES BY WEDNESDAY
AFTERNOON AS THE TROUGH PASSES OVERHEAD...BACK INTO THE DOLDRUMS.
TROUGHINESS WILL REMAIN OVER CALIFORNIA INTO NEXT WEEKEND RETURNING
THE AREA TO WHAT HAS BECOME TYPICAL FOR THIS SUMMER...COOL...DRIZZLEY
AND GRAY.
&&
.AVIATION...AS OF 4:45 PM PDT SUNDAY...LOW PRESSURE DIVING INTO THE
GREAT BASIN COMBINED WITH A THERMAL TROUGH DEVELOPING OVER
CALIFORNIA WILL RESULT IN OFFSHORE FLOW THIS EVENING. THE OFFSHORE
FLOW WILL PRECLUDE ANY FORMATION OF STRATUS FROM THE TERMINALS
OVER THE NEXT 24 HOURS. HOWEVER...THERE WILL BE A POSSIBILITY
OF A BRIEF PERIOD OF CIGS AT THE MONTEREY AND SALINAS TERMINALS LATE
TONIGHT AS THE MARINE LAYER LINGER AROUND 1200 FEET IN THIS AREA.
.VICINITY OF KSFO...VFR TONIGHT THROUGH MONDAY EVENING. WEST WINDS
20 KT GRADUALLY DIMINISHING AFTER SUNSET.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...VFR WITH SOME PATCHY FOG DEVELOPING LATE
THIS EVENING. A PERIOD OF LIFR WILL BE POSSIBLE BETWEEN 1200Z AND
1600Z MONDAY MORNING. WEST WINDS 10 TO 15 KT DIMINISHING AFTER
SUNSET.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...GLW...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
&&
$$
PUBLIC FORECAST: EVANS
AVIATION/MARINE: LARRY
000
FXUS65 KPSR 052245
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
345 PM MST SUN SEP 5 2010
.SYNOPSIS...
THE WEATHER PATTERN WILL CHANGE DURING THE NEXT FEW DAYS...WITH LOW
PRESSURE ALOFT BECOMING THE DOMINANT WEATHER FEATURE OVER THE
WESTERN UNITED STATES. CONSEQUENTLY...TEMPERATURES WILL TREND
DOWNWARD DURING MUCH OF THE WORK WEEK WITH BELOW NORMAL READINGS
LIKELY WEDNESDAY THROUGH FRIDAY. THE BEST CHANCE OF SHOWERS AND
THUNDERSTORMS WILL OCCUR OVER SOUTH-CENTRAL ARIZONA MONDAY NIGHT
THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
QUIET CONVECTION TODAY AS ANTICIPATED. LITTLE CHANGE IN AFTERNOON
TEMPS OVERALL...WITH SOME SLIGHT COOLING IN SOUTHWEST ARIZONA AND
SOUTHEAST CALIFORNIA. HIGH PRESSURE WILL CONTINUE TO WEAKEN AS
TROUGHING TO THE NORTHWEST ADVANCES EASTWARD. MODELS CONTINUE TO
SHOW A PERTURBATION IN THE FLOW NEAR THE BAJA COAST GETTING CAUGHT
UP IN THE INCREASING WESTERLY FLOW. CYCLONIC FLOW ASSOCIATED WITH
THE FEATURE WILL LEAD TO NORTHWARD ADVECTION OF MOISTURE FROM SONORA
TONIGHT AND MONDAY...MAINLY FOR EASTERN PORTIONS OF OUR FORECAST
AREA...WITH MOISTURE REMAINING THROUGH AT LEAST TUESDAY. NAM AND GFS
DIFFER ON THE QPF WITH THE GFS BEING MORE GENEROUS. NEITHER MODEL
HAS MUCH IN THE WAY OF QG FORCING OR INSTABILITY SO THE MORE MODEST
NAM QPF MAKES MORE SENSE. IT IS INDICATING SUBSTANTIAL CONVECTIVE
ACTIVITY OVER PIMA AND SANTA CRUZ COUNTIES MONDAY WITH
REMNANT/DEBRIS SHOWERS DRIFTING NORTHWARD MONDAY NIGHT. IT
REDEVELOPS CONVECTION TUESDAY AFTERNOON AS DAYTIME DESTABILIZATION
OCCURS AND THE LARGE TROUGH IN THE WESTERLIES SAGS SOUTHWARD. THE
GFS SEEMS TO PEAK THE QPF LATE MONDAY NIGHT AND DECREASE IT DURING
THE DAY...WITHOUT MUCH IN THE WAY OF REDEVELOPMENT. THIS SCENARIO
SEEMS LESS SOUND...ESPECIALLY SINCE ITS FORECAST SOUNDINGS ARE MORE
UNSTABLE TUESDAY AFTERNOON THAN MONDAY NIGHT AND THERE ARENT ANY
DEEP SATURATED LAYERS BEING DEPICTED. MEANWHILE TEMPERATURES WILL BE
ON THE DECLINE. THE LARGE TROUGH IN THE WESTERLIES DEEPENS WEDNESDAY
FOR ADDITIONAL COOLING IN OUR WESTERN AREAS...THOUGH THE TROUGH AXIS
IS STILL TO OUR WEST...FOR MAX TEMPS ON THE LOWER DESERTS CLOSE TO
100. MUCH DRIER AIR WILL BEGIN TO PUSH INTO ARIZONA ON WEDNESDAY AS
WELL.
IN THE EXTENDED...THE TROUGH MOVES ACROSS THE INTERMOUNTAIN WEST AND
ROCKIES THURSDAY AND FRIDAY FOR A BIT OF ADDITIONAL COOLING WITH
HIGHS ON THE LOWER DESERTS IN THE MID AND UPPER 90S. DRY AIR WILL
OVERSPREAD THE ENTIRE SOUTHWESTERN U.S. AS WELL. TEMPS WILL BEGIN TO
INCREASE NEXT WEEKEND AS THE RIDGE CENTERED OVER THE
SOUTH-CENTRAL UNITED STATES STRENGTHENS AND EXPANDS TOWARD THE
WEST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
TYPICAL DIURNAL WINDS WITH FEW TO SCATTERED CLOUDS BETWEEN 10 AND 12
THOUSAND FEET THROUGH MONDAY.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKIES ARE EXPECTED THROUGH TUESDAY. WINDS GUSTING TO BETWEEN
20 AND 25 KNOTS ARE EXPECTED FROM THE SOUTH AT KBLH THIS AFTERNOON
AND EARLY THIS EVENING AND FROM THE WEST AT KIPL THIS EVENING.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS EAST OF GLOBE
WEDNESDAY. OTHERWISE...LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS
EXPECTED TO DEVELOP NEAR THE WEST COAST WITH COOLER WEATHER
WEDNESDAY. THIS SYSTEM IS ALSO EXPECTED TO RESULT IN BREEZY WEATHER
FROM THE SOUTHWEST WEDNESDAY AFTERNOON WITH GUSTS BETWEEN 20 AND 30
MPH. SOMEWHAT BELOW AVERAGE TEMPERATURES FOR EARLY SEPTEMBER AND DRY
AIR ARE EXPECTED THROUGH THE PERIOD WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ
AVIATION...ELLIS
FIRE WEATHER...ELLIS
000
FXUS66 KSTO 052222
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
320 PM PDT SUN SEP 5 2010
.DISCUSSION...
UPPER RIDGE CONTINUES TO FLATTEN AS AN UPPER TROUGH MOVES THROUGH
THE PACIFIC NORTHWEST. NORTHERLY SURFACE PRESSURE GRADIENT HAS
REMAINED AT AN ELEVATED LEVEL...PARTICULARLY FROM MFR TO RDD. AS
SUCH...LOCALLY GUSTY WINDS UPWARDS OF 30-35 MPH HAVE BEEN OBSERVED
FOR MUCH OF THE DAY FROM ABOUT CORNING NORTHWARD. THE COLD AIR
ADVECTION ASSOCIATED WITH THIS FLOW HAS KEPT MOST LOCATIONS COOLER
THAN YESTERDAY. THE EXCEPTION LIES WITH AREAS ADJACENT TO THE
DELTA...WHERE A WEAKER ONSHORE BREEZE (AND NO STRATUS OBSERVED ON
VISIBLE SATELLITE) HAS ALLOWED TEMPERATURES TO WARM.
THE UPPER TROUGH SHIFTS EASTWARD TONIGHT AND THE SURFACE PRESSURE
GRADIENT WILL BECOME NORTHEASTERLY IN RESPONSE. WILL LIKELY SEE SOME
LOCALLY GUSTY CONDITIONS DOWN NE/SW ORIENTED SIERRA CANYONS TONIGHT
INTO EARLY MONDAY.
A BRIEF SHORTWAVE RIDGE WILL MOVE THROUGH LABOR DAY
MONDAY...BRINGING A FEW DEGREES OF ATMOSPHERIC WARMING TO SLIGHTLY
WARMER THAN AVERAGE LEVELS. TUESDAY WILL BRING COOLING OF A FEW
DEGREES FROM MONDAYS HIGHS AS A GULF OF ALASKA TROUGH BEGINS TO DIG
SOUTHWARD.
THE MORE SIGNIFICANT COOLING OCCURS ON WEDNESDAY AS THE UPPER TROUGH
CONTINUES TO AMPLIFY ALONG THE WEST COAST. HPC STANDARDIZED ANOMALY
CHARTS CONTINUE TO ADVERTISE THE 500MB HEIGHTS OF THIS SYSTEM AS 3
TO 4 DEVIATIONS LOWER THAN NORMAL. THIS WOULD PUT IT ALONG SIMILAR
LINES AS THE SYSTEM THAT MOVED THROUGH LAST WEEKEND AND BROUGHT
LIGHT SHOWERS TO PARTS OF THE VALLEY AND MOUNTAINS. CURRENT MODEL
PROGS ARE A BIT MORE PROGRESSIVE THAN PREVIOUS RUNS...AND WILL
REFRAIN FROM TRENDING IN A SIMILAR FASHION FOR THE TIME BEING.
VALLEY HIGHS WILL ONLY REACH THE 70S ON WED WITH 50S AND 60S OVER
THE MOUNTAINS. IF THE SHOWERS DO PAN OUT...WOULDN`T BE SURPRISED TO
SEE A DUSTING OF SNOW TOWARDS THE HIGHEST ELEVATIONS OF LASSEN PEAK.
DANG
.EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)...
CURRENT MEDIUM RANGE MODEL PROGS SHIFT THE UPPER TROUGH EAST INTO
THE GREAT BASIN THURSDAY AND REPLACE THE PATTERN WITH A WEAK ZONAL
FLOW WITH BENIGN WEATHER. ENOUGH MOISTURE AND WEAK INSTABILITY MAY
LINGER BEHIND THE TROUGH TO GENERATE SOME WEAK SHOWERS OVER NORTHERN
MTNS. JCLAPP
.AVIATION...
VFR CONDS NEXT 24 HOURS. NORTHERLY WINDS CONTINUE INTO MON OVER NRN
MTNS AND NRN SAC VALLEY DUE TO TIGHTENING OFFSHORE PRESSURE
GRADIENT. EXPECT GUSTY W-NW WINDS ALOFT. JCLAPP
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS65 KREV 052215
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
315 PM PDT SUN SEP 5 2010
.SHORT TERM...
AN UPPER LOW IS SWIFTLY MOVING THROUGH IDAHO AND WESTERN MONTANA
THIS AFTERNOON. THE MAIN COLD AIR ADVECTION ASSOCIATED WITH THE
LOW WILL BE OVER CENTRAL AND EASTERN NEVADA WITH THE MAIN SURFACE
HIGH SETTLING ACROSS FAR NORTHEASTERN NEVADA BY EARLY MONDAY MORNING.
HOWEVER...MODEST HIGH PRESSURE WILL BACKDOOR INTO WESTERN NEVADA
AND NORTHEAST CALIFORNIA TONIGHT WITH THE NAM SHOWING -8 MB OF
SURFACE GRADIENT FROM SACRAMENTO TO RENO BY 12Z/5 AM MONDAY. AS THE
COLD AIR ADVECTION IS MODEST OVER THE SIERRA...THE EASTERLY WIND
EVENT ON LAKE TAHOE MAY BE SHORTER-LIVED THAN PREVIOUSLY THOUGHT
WITH THE BEST CHANCE FOR STRONG NE-E WINDS NOW LOOKING LIKE FROM
LATE EVENING UNTIL AROUND 5 AM MONDAY. HOWEVER...I WILL LEAVE THE
LAKE WIND ADVISORY UNTIL 10 AM MONDAY WITH SOME UNCERTAINTY AS TO
WHEN THE HIGHER WIND CHANCES WILL DIMINISH (AND WITH IT BEING A
HIGH IMPACT PERIOD FOR LAKE TAHOE ACTIVITIES).
MONDAY...ANY SIGNIFICANT EASTERLY WINDS SHOULD DECREASE BY EARLY-
MID MORNING WITH LIGHT FLOW IN THE AFTERNOON. WITH DRY AIR AND
LIGHT WINDS...TEMPERATURES MONDAY MORNING WILL BOTTOM OUT IN THE
UPPER 20S TO LOWER 30S FOR THE SIERRA VALLEY (NORTH OF TRUCKEE)
AND OVER TO AROUND PORTOLA. BY AFTERNOON...A VERY NICE LABOR DAY
IS ON TAP WITH HIGHS REBOUNDING INTO THE 70S UNDER SUNNY SKIES FOR
MOST VALLEYS.
TUESDAY...WINDS PICK UP AGAIN BY AFTERNOON AS ANOTHER UPPER LOW
APPROACHES THE REGION. THE INCREASED WINDS/MIXING WILL BRING A
REBOUND OF 5 TO 10 DEGREES FOR MOST LOCATIONS OUTSIDE OF THE SIERRA.
TUESDAY NIGHT LOOKS MUCH MILDER LOWS FOR THE VALLEYS AS INCREASED
MOISTURE AND GUSTY RIDGE WINDS HOLD DOWN DECOUPLING.
WEDNESDAY...THE UPPER LOW WILL SWING THROUGH THE REGION DRAGGING A
COLD FRONT THROUGH THE ENTIRE CWA WEDNESDAY NIGHT. HIGHS WEDNESDAY
WILL BE BELOW AVERAGE AS COLDER AIR ALOFT FILTERS INTO THE REGION.
PRECIP WISE...THE FOCUS WILL BE ACROSS THE NORTHERN AND NORTHWESTERN
CWA LATE TUESDAY NIGHT AND WEDNESDAY WITH THE COLD FRONT FOCUSING
PRECIP THERE. ELSEWHERE...IT LOOKS LIKE MAINLY A WIND SITUATION
WITH THE PRE-FRONTAL AIRMASS SHOWING ONLY SHALLOW MOISTURE WHICH
WILL TEND TO KEEP SHOWERS CONFINED TO NEAR THE SIERRA AND ACROSS
FAR NORTHWEST NEVADA NEAR THE LOW LEVEL COLD FRONT.
AS THE FRONT DRIVES SOUTH AND EAST WITH THE CORE OF THE UPPER LOW
WEDNESDAY NIGHT...AREAS FURTHER SOUTH WILL HAVE A CHANCE OF PRECIP
AS THE ATMOSPHERE MOISTENS UP WITH INCREASED UPPER FORCING.
SNYDER
.LONG TERM...THURSDAY THROUGH SUNDAY...
LITTLE CHANGE TO THE GOING FORECAST WITH UNSETTLED WEATHER ON
THURSDAY. FRIDAY INTO THE WEEKEND WILL BE FALL LIKE WITH MILD
CONDITIONS AND MODERATING TEMPERATURES...ALTHOUGH THEY WILL STAY
BELOW NORMAL FOR THE PERIOD.
ELONGATED UPPER TROUGH WILL EXTEND FROM THE PACNW INTO NW NEVADA
SOUTH TO THE TAHOE BASIN EARLY THURSDAY...LIFTING OFF TO THE
NORTHEAST THURSDAY EVENING. THE OPERATIONAL EC AND GFS RUNS HAD COME
CLOSER IN LINE BUT THE LATEST OPERATIONAL GFS IS NOW A GOOD 12 HOURS
FASTER WITH THE TROUGH. WILL CONTINUE TO LEAN TOWARD THE SLOWER EC
AS THE TROUGH IS RELATIVELY DEEP AND COLD WHICH INTUITIVELY WOULD
POINT TO THE SLOWER SOLUTION. THE TROUGH IS NOT INDICATED TO BE
QUITE AS COLD WITH 700MB TEMPERATURES DOWN TO -2C. SHOWERS WILL BE
MOST NUMEROUS NORTH OF INTERSTATE 80 ALTHOUGH A LITTLE LIGHT SNOW
MIGHT BE POSSIBLE FOR THE HIGHEST PEAKS AROUND THE TAHOE BASIN. ALSO
EXPECT BREEZY WEST-NORTHWEST WINDS IN THE WAKE OF THE TROUGH
THURSDAY AFTERNOON AND EVENING.
FOR FRIDAY THROUGH THE WEEKEND THE UPPER FLOW WILL BE GENERALLY
ZONAL WITH GRADUALLY INCREASING HEIGHTS. BY SUNDAY MEDIUM RANGE
MODELS DIVERGE SOMEWHAT ALTHOUGH THE TREND IS TO DEVELOP A TROUGH
ALONG THE WEST COAST WITH WEST TO SOUTHWEST FLOW ALOFT. WILL
CONTINUE DRY FORECAST FOR THIS PERIOD WITH TEMPERATURES SLOWLY
MODERATING TO JUST BELOW NORMAL BY SUNDAY. JAH
&&
.AVIATION...
VFR AT TAF SITES. FRONT PUSHED THROUGH KRNO AREA THIS MORNING
RESULTING IN NORTH AFTERNOON WINDS. WINDS WILL CONTINUE TO VEER TO
AN EASTERLY DIRECTION TONIGHT WITH EAST WINDS AGAIN MONDAY. JAH
&&
.FIRE WEATHER...
WILL ISSUE A FIRE WEATHER WATCH FOR TUESDAY AFTERNOON INTO EARLY
EVENING IN PARTS OF WRN NV AND NERN CA AS INDICATED IN THE
WATCH/WARNING SEGMENT BELOW. TIGHTENING GRADIENT AHEAD OF NEXT TROF
WILL LEAD TO INCREASED WINDS BY TUES AFTN ACROSS THE REGION.
CONFIDENCE IS HIGHEST FOR ZONE 450 TO MEET BOTH RH AND WIND CRITERIA
FOR THE NECESSARY DURATION. ZONE 453 WILL CERTAINLY BE DRY ENOUGH
WITH A BIT MORE UNCERTAINTY ON DURATION AND MAGNITUDE OF STRONGER
WIND GUSTS...WHILE FOR 458/278 THE SOUTHERN HALF OF EACH ZONE HAS
BEST POTENTIAL FOR REACHING BOTH WIND AND RH CRITERIA. WITH GUIDANCE
INDICATING A RAPID RISE IN HUMIDITY TUESDAY EVENING THIS EVENT
SHOULD BE SHORTER LIVED...BUT A 3-6 HOUR WINDOW OF OPPORTUNITY
EXISTS FOR CRITICAL FIRE WEATHER CONDITIONS IN THE WATCH AREA.
FARTHER SOUTH...MORE UNCERTAINTY EXISTS TO WHETHER WINDS WILL
INCREASE SUFFICIENTLY BY TUES AFTN...ALTHOUGH POTENTIAL FOR STRONGER
WINDS EXISTS TUES NIGHT WITH HUMIDITY ALSO RISING. MEANWHILE FROM
TAHOE NORTHWARD ACROSS WRN LASSEN COUNTY AND SURPRISE VALLEY...THE
HUMIDITY IS LESS LIKELY TO REMAIN LOW ENOUGH FOR ENOUGH TIME BY THE
TIME THE WINDS KICK IN AND ADVECT MORE MOISTURE. THEREFORE THESE
AREAS WERE LEFT OUT OF THE WATCH AT THIS TIME. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING NVZ450-453-458.
LAKE WIND ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT MONDAY
FOR LAKE TAHOE IN NVZ002.
CA...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING CAZ278.
LAKE WIND ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT MONDAY
FOR LAKE TAHOE IN CAZ072.
&&
$$
HTTP://WEATHER.GOV/RENO
000
FXUS66 KHNX 052139
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
239 PM PDT SUN SEP 5 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN AS A TROUGH OF LOW
PRESSURE BRUSHES THE REGION TODAY. THIS WILL BRING A SLIGHT COOLING
TREND THROUGH LABOR DAY. A STRONGER LOW PRESSURE SYSTEM WILL THEN
PROVIDE A MORE SIGNIFICANT COOL DOWN BY MIDWEEK AS IT PUSHES
THROUGH.
&&
.DISCUSSION...
CLEAR DRY CONDITIONS ACROSS THE REGION WITH TEMPERATURES A FEW
DEGREES COOLER. COOLING MAINLY DUE TO AN UPPER TROUGH MOVING EAST
THROUGH THE PAC NW. MARINE LAYER REMAINED SHALLOW AND CLEARED
OVERNIGHT DUE BUILDING SURFACE HIGH IN NORTH CAL BEHIND UPPER
TROUGH. THE SURFACE HIGH WILL SHIFT TOWARDS THE GREAT BASIN MONDAY
RESULTING IN AN OFFSHORE FLOW. THIS WILL PROVIDE CLEAR AND DRY
CONDITIONS WITH LITTLE CHANGE IN TEMPERATURES. MORE SIGNIFICANT
COOLING WILL BEGIN TUESDAY AS ONSHORE FLOW INCREASES AHEAD OF A
DEEPER UPPER TROUGH. THE UPPER TROUGH WILL MOVE SOUTH DOWN THE PAC
NW COAST TUESDAY THAN TURN EAST TUESDAY NIGHT INTO NORTH
CALIFORNIA. STRONGER PRESSURE GRADIENTS AND ONSHORE FLOW WILL
BRING COOL MARINE AIR INTO THE INTERIOR CALIFORNIA TUESDAY
AFTERNOON. STRONG GUSTY WINDS WILL POSSIBLE THROUGH THE COASTAL
MOUNTAINS PASSES OF THE VALLEY THROUGH TUESDAY NIGHT. THE UPPER
TROUGH AXIS WILL PUSH THROUGH CENTRAL CALIFORNIA WEDNESDAY. BREEZY
CONDITIONS SHOULD DEVELOP WEDNESDAY IN THE SAN JOAQUIN VALLEY AS
THE UPPER JET ALIGNS WITH THE ONSHORE GRADIENTS. EXPECT WINDY
CONDITIONS IN THE KERN COUNTY MOUNTAINS AND DESERT FROM NOON
WEDNESDAY AND WEDNESDAY NIGHT. SOME LIGHT PRECIPITATION MAY BE
POSSIBLE OVER THE SIERRA WEDNESDAY INTO THURSDAY MORNING. BUT DO
NOT HAVE A HIGH DEGREE OF CONFIDENCE. GFS MODEL IS TRENDING DRIER
AND ECWM PROGS SOME QPF OVER THE SIERRA. A COLDER AIRMASS WILL
RESULT IN WELL BELOW NORMAL TEMPERATURES WEDNESDAY AND THURSDAY.
TEMPERATURES START TO WARM FRIDAY BUT A WEST FLOW ALOFT MAY
MAINTAIN BELOW SEASONAL TEMPERATURES FOR THE REMAINDER OF THE
WEEK.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 00Z TUESDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BINGHAM
SYNOPSIS...BSO
WEATHER.GOV/HANFORD
000
FXUS66 KMTR 052130
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
230 PM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 2:15 PM PDT SUNDAY...AN OFFSHORE FLOW WILL
DEVELOP TONIGHT PRODUCING GUSTY NORTH TO NORTHEAST WINDS OVER THE
HIGHER TERRAIN. A WARM AIRMASS WILL ACCOMPANY THE OFFSHORE FLOW
PROVIDING A WARM LABOR DAY. ALSO...THE SKY WILL REMAIN CLEAR...
EXCEPT IN AND AROUND THE MONTEREY BAY TONIGHT AND MONDAY MORNING.
TEMPERATURES AT 850MB ARE AROUND 22 DEGREES CELSIUS WHICH WILL
PROMOTE AFTERNOON HIGHS ON LABOR DAY IN THE 70S NEAR THE COAST...80S
AROUND THE SAN FRANCISCO BAY...90S INLAND VALLEYS AND EVEN UP TO 105
IN THE INTERIOR VALLEYS OF MONTEREY AND SAN BENITO COUNTIES. THE
WARMTH WILL BE SHORT LIVED HOWEVER AS A TROUGH MOVES QUICKLY TOWARD
CALIFORNIA. 850MB TEMPERATURES DROP FROM 22 DEGREES MONDAY
AFTERNOON TO 15 DEGREES TUESDAY AFTERNOON AS THE TROUGH APPROACHES.
THEN THE 850MB TEMPERATURE DROPS TO 10 DEGREES BY WEDNESDAY
AFTERNOON AS THE TROUGH PASSES OVERHEAD...BACK INTO THE DOLDRUMS.
TROUGHINESS WILL REMAIN OVER CALIFORNIA INTO NEXT WEEKEND RETURNING
THE AREA TO WHAT HAS BECOME TYPICAL FOR THIS SUMMER...COOL...DRIZZLEY
AND GRAY.
&&
.AVIATION...AS OF 10:45 AM PDT SUNDAY...DEVELOPING OFFSHORE FLOW HAS
CLEARED STRATUS FROM SF BAY REGION. LINGERING LOW CLOUDS AROUND MRY
BAY TO CLEAR SHORTLY WITH LOOK OUT THE WINDOW REVEALING NO CIG AT
KMRY.
.VICINITY OF KSFO...VFR TODAY THROUGH MONDAY MORNING. NW WIND GUSTS
THIS AFTERNOON AND EVENING TO REMAIN UNDER 20 KT.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...LOW CIGS TO HAVE CLEARED BY 18Z FROM TAF
SITES. LOW CLOUD POOL IN MONTEREY BAY MAY BE TOUGH TO CLEAR OUT
WITH OFFSHORE WINDS RIDING ON TOP OF THE SHALLOW INVERSION. HOWEVER
EXPECT COMPLETE CLEARING EVEN AT KWVI TODAY. HAVE PUT TEMPO GROUPS
FOR SHALLOW MARINE LAYER WITH REDUCED CIGS TO RETURN LATE TONIGHT
INTO EARLY MONDAY MORNING. THIS IS MEDIUM CONFIDENCE AS OFFSHORE
FLOW MAY BE STRONG ENOUGH TO COMPLETELY SCOUR THINGS OUT AND GIVE
KMRY AND KSNS A VFR START LABOR DAY MORNING. WILL ASSESS TRENDS THIS
AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...GLW...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
&&
$$
PUBLIC FORECAST: EVANS
AVIATION/MARINE: RWW
000
FXUS66 KEKA 052051
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
151 PM PDT SUN SEP 5 2010
.SYNOPSIS...MAINLY CLEAR CONDITIONS ARE EXPECTED FOR TONIGHT AND
MONDAY AS WINDS KEEP THE MARINE LAYER OFFSHORE. A LARGE UPPER
LEVEL TROUGH WILL BRING COOLER WEATHER AND A CHANCE OF SHOWERS TO
NORTHWEST CALIFORNIA FOR MID WEEK
&&
.DISCUSSION...AFTERNOON SURFACE ANALYSIS DEPICTS A TIGHT PRESSURE
GRADIENT (7+MB) ACROSS THE CWA...BETWEEN THERMAL LOW TO SOUTHEAST
AND HIGH PRESSURE AXIS TO THE NORTH. WATER VAPOR SHOWS UPPER
TROUGH PASSING TO THE NORTHEAST OF OUR FA. THIS PLACEMENT WILL
RESULT IN A THERMAL TROUGH ACROSS OUR NORTHERN ZONES TONIGHT INTO
MONDAY. NORTHEAST OFFSHORE WINDS WILL STRENGTHEN AS
WELL...HINDERING DECOUPLING POTENTIAL OVERNIGHT. THIS SET-UP DOES
BRING ELEVATED FIRE WEATHER CONCERNS GIVEN GUSTY RIDGE-TOPS WINDS
AND POOR HUMIDITY RECOVERIES...AND WILL CONTINUE HEADLINE IN THE
FIRE WEATHER FORECAST ACCORDINGLY.
FOR MID-WEEK...LARGE UPPER TROUGH WILL PIVOT SOUTH ACROSS THE
PACIFIC NORTHWEST. LIFT AND THERMAL DYNAMICS WILL BE STRONG ENOUGH
TO PRODUCE SOME CONVECTIVE SHOWERS...MAINLY NORTHERN ZONES THROUGH
THURSDAY. MUCH COOLER WEATHER WILL ENSURE...HOWEVER LAPSE RATES
WILL NOT BE STEEP ENOUGH TO RESULT IN THUNDERSTORM ACTIVITY.
NORTHWESTERLY ONSHORE FLOW THEN LOOKS TO SET-UP FOR THE WEEKEND.
HENRY
&&
.AVIATION...A TIGHT SURFACE PRESSURE GRADIENT ALONG THE NORTHWEST
CALIFORNIA COAST WILL CONTINUE TO BRING GUSTY NORTHWEST WINDS TO
THE COASTAL AIRSTRIPS THIS EVENING. GUSTS UP TO 30 KT ARE POSSIBLE
BEFORE THE WINDS DIMINISH OVERNIGHT. INLAND THE WINDS COULD BECOME
GUSTY OVER THE RIDGETOPS. VFR IS EXPECTED FOR ALL
LOCATIONS...HOWEVER SOME STRATUS MAY FORM AROUND HUMBOLDT BAY
DURING THE NIGHT. STROZ
&&
.MARINE...A TIGHT SURFACE PRESSURE GRADIENT WILL CONTINUE TO BRING
STRONG NORTH WINDS TO THE WATERS THROUGH MONDAY. MORNING SHIP
REPORTS SHOWED GALES ACROSS THE OUTER WATERS AND THE AFTERNOON
BUOY OBSERVATIONS REFLECT THIS. THE STRONGEST WINDS WILL BE THIS
EVENINGS OVER THE OUTER WATERS WITH SUSTAINED WINDS OF 25 TO 35 KT
AND GUSTS UP TO 45 KT. SEAS THERE WILL PEAK NEAR 15 FT AROUND 8
SECONDS TONIGHT. SO THE GALE AND HAZARDOUS SEAS WARNINGS REMAIN
ONGOING FOR THE OUTER WATERS THROUGH MONDAY. FOR THE INNER WATERS,
SCA REMAIN UP DUE TO WINDS AND STEEP SHORT PERIOD SEAS PROPAGATING
IN FROM THE OUTER WATERS. THE PRESSURE GRADIENT WILL START TO
WEAKEN A LITTLE MONDAY ALLOWING WINDS AND SEAS TO DROP SOME, BUT
NOT MUCH. THE GRADIENT WILL REALLY WEAKEN LATE MONDAY INTO
TUESDAY, ALLOWING WINDS TO FALL AND SEAS TO SUBSIDE. LIGHT TO
MODERATE NORTH WINDS AND SEAS BELOW 10 FT ARE EXPECTED TUESDAY
THROUGH THE END OF THE FORECAST PERIOD. STROZ
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
GALE WARNING FOR PZZ470-475.
HAZARDOUS SEAS WARNING FOR PZZ455-470-475.
SMALL CRAFT ADVISORY FOR PZZ450-455.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS66 KSGX 052030
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
200 PM PDT SUN SEP 5 2010
.SYNOPSIS...
A COOLING TREND BEGINS TODAY AND CONTINUES THROUGH THURSDAY WITH A
DEEPER MARINE LAYER FOR MORE EXTENSIVE NIGHT AND MORNING COASTAL LOW
CLOUDS AND FOG. LOCALLY WINDY AT TIMES IN THE MOUNTAINS AND DESERTS.
A LITTLE WARMER FOR FRIDAY THROUGH NEXT WEEKEND UNDER WEAKER LOW
PRESSURE.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THIS AFTERNOON...RECENT AIRCRAFT SOUNDINGS SHOW THE MARINE LAYER NOW
JUST OVER 1000 FEET DEEP WITH LOW CLOUDS AND FOG LINGERING AT THE
BEACHES. A COASTAL EDDY HAS DEVELOPED AND WILL HELP TO DEEPEN THE
MARINE LAYER THROUGH TONIGHT.
A TROUGH OF LOW PRESSURE MOVING INLAND THROUGH THE PACIFIC NORTHWEST
WILL CONTINUE TO INCREASE THE ONSHORE FLOW IN SOUTHWEST CALIFORNIA
BRINGING A FEW DEGREES OF COOLING FOR MOST AREAS TODAY...WITH THE
MOST COOLING IN SOME VALLEY AND INLAND COASTAL AREAS. THE STRONGER
ONSHORE FLOW WILL BRING GUSTY WEST WINDS TO THE MOUNTAINS AND
DESERTS FOR LATE AFTERNOON THROUGH LATE EVENING.
FOR MONDAY...CONTINUED SLOW COOLING AND DEEPENING OF THE MARINE
LAYER UNDER WEAK LOW PRESSURE WITH A COASTAL EDDY.
FOR TUESDAY THROUGH THURSDAY...ANOTHER TROUGH OF LOW PRESSURE WILL
DEEPEN ALONG THE WEST COAST...LOWERING TEMPERATURES TO WELL BELOW
SEASONAL AVERAGES...AND DEEPENING THE MARINE LAYER FOR MORE
EXTENSIVE NIGHT AND MORNING LOW CLOUDS. INCREASING ONSHORE PRESSURE
GRADIENTS WILL PRODUCE GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS
AT TIMES...ESPECIALLY ON THURSDAY.
FOR FRIDAY THROUGH NEXT WEEKEND...SLOW WARMING UNDER WEAKER LOW
PRESSURE.
&&
.AVIATION...
051900Z...MARINE LAYER ABOUT 1500 FT AND GOING UP TO ABOUT 2K FT
PLUS TONIGHT AS EDDY CRANKS UP. BASES AROUND 1K TO 1500 FT TONIGHT
THROUGH MONDAY MORNING. MARINE LAYER INCREASING THROUGH MONDAY INTO
TUESDAY. AREAS OF VSBY 1-2SM OR LESS INLAND LATE TONIGHT THROUGH
MONDAY MORNING. STRATUS/FOG EXPECTED TO MOVE BACK INTO THE COASTAL
AIRPORTS ABOUT 06Z. EXPECT STRATUS/FOG TO CLEAR TO THE COAST 18-19Z
MONDAY. STRATUS AND FOG EXPECTED TO REMAIN ALONG THE COAST THROUGH
MONDAY AFTERNOON AND MOVE INTO THE COASTAL AREAS MID TO LATE
AFTERNOON.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...PG
AVIATION/MARINE...WHITLOW
NWS ON THE WEB AT WEATHER.GOV/SANDIEGO
000
FXUS65 KPSR 052015
AFDPSR
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PHOENIX AZ
115 PM MST SUN SEP 5 2010
.UPDATE...
UPDATED AVIATION SECTION.
&&
.SYNOPSIS...
EXPECT ANOTHER HOT DAY TODAY AS HIGH PRESSURE ALOFT PERSISTS OVER
THE SOUTHWEST UNITED STATES. THE WEATHER PATTERN WILL CHANGE DURING
THE NEXT FEW DAYS...WITH LOW PRESSURE ALOFT BECOMING THE DOMINANT
WEATHER FEATURE OVER THE WESTERN UNITED STATES. CONSEQUENTLY...
TEMPERATURES WILL TREND DOWNWARD DURING MUCH OF THE UPCOMING WEEK
WITH BELOW NORMAL READINGS LIKELY WEDNESDAY THROUGH FRIDAY. THE BEST
CHANCE OF SHOWERS AND THUNDERSTORMS WILL OCCUR OVER SOUTH-CENTRAL
ARIZONA MONDAY NIGHT THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
MORNING SOUNDINGS SHOW DRYING AT PSR AND TWC COMPARED TO
YESTERDAY...WITH MOISTENING AT FGZ. ALL OF THEM SHOW ADDITIONAL
WARMING ALOFT...GENERALLY BETWEEN 600 MB AND 450 MB. LATEST
RUC/NAM/GFS FORECAST SOUNDINGS SHOW CONDITIONS REMAINING TOO STABLE
TODAY FOR THUNDERSTORMS OVER OUR FORECAST AREA. THEY ALSO GO ON TO
SHOW MOISTENING TONIGHT AND MONDAY OVER SOUTH-CENTRAL ARIZONA ALONG
WITH A LITTLE BIT OF COOLING ALOFT. FORECAST SOUNDINGS ALSO INDICATE
MAX TEMPS WILL HAVE LITTLE CHANGE TODAY OVER SOUTH-CENTRAL ARIZONA
WITH SLIGHT COOLING OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.
NO UPDATES. MORE LATER.
PREVIOUS DISCUSSION...
HIGH PRESSURE ALOFT WILL BRING ABOVE NORMAL DAYTIME HIGHS AGAIN
TODAY...THOUGH FORECAST SOUNDINGS SUGGEST MAX TEMPS WILL BE A COUPLE
DEGREES LOWER THAN WHAT OCCURRED SATURDAY. UPPER AIR PATTERN WILL
UNDERGO A SIGNIFICANT CHANGE DURING THE NEXT FEW DAYS...AS LOW
PRESSURE ALOFT BECOMES THE DOMINANT WEATHER FEATURE OVER THE WESTERN
UNITED STATES WHILE THE SUBTROPICAL HIGH IS SUPPRESSED FAR TO OUR
SOUTH AND EAST. A RATHER STRONG LOW PRESSURE SYSTEM AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...AND BRING DRY AND COOLER AIR TO THE REGION. 12Z 850 MB
TEMPS FORECAST TO LOWER FROM 26C TODAY TO 17-18C BY THURSDAY/
FRIDAY...WHEN BELOW NORMAL MAX AND MIN TEMPS ARE A GOOD BET. THIS
WEATHER CHANGE HAS BEEN WELL-ADVERTISED FOR SEVERAL DAYS NOW.
PRECIPITATION CHANCES DURING THIS TRANSITION HAVE BEEN TOUGHER TO
DEAL WITH...AS NUMERICAL MODELS THE PAST FEW DAYS HAVE PROVIDED
WIDELY DIVERGENT SOLUTIONS REGARDING DEGREE OF MOIST ADVECTION AND
STRENGTH/TRACK OF A WEAK WEATHER DISTURBANCE EMANATING FROM THE
SUBTROPICS IN ADVANCE OF THE AFOREMENTIONED LOW PRESSURE SYSTEM/COLD
FRONT. NAM/ECMWF/GFS HAVE NOW CONVERGED ON WHAT APPEARS TO BE A
REASONABLE SOLUTION...WITH MOIST ADVECTION OCCURRING PRIMARILY OVER
SOUTH-CENTRAL AZ MONDAY AFTN INTO TUESDAY AS WEAK DISTURBANCE
APPROACHES FROM THE SOUTHWEST. AT THE SAME TIME...UPPER LEVEL JET
STREAK ASSOCIATED WITH THE STRONG LOW PRESSURE SYSTEM STRENGTHENS TO
OUR NORTH...WITH EASTERN HALF OF OUR FORECAST AREA UNDER RIGHT-REAR
QUAD. MODEST DEGREE OF CAPE EXISTS IN FORECAST SOUNDINGS BY TUESDAY
MORNING...SO THUNDERSTORM POTENTIAL SHOULD EXIST. INTRODUCED SLIGHT
CHANCE OF SHOWERS/THUNDERSTORMS MAINLY OVER SOUTH-CENTRAL AZ MONDAY
NIGHT THROUGH TUESDAY EVENING (PRECIP CHANCES MAY BE TOO
CONSERVATIVE...BUT AT LEAST PRECIP CHANCE HAS BEEN INTRODUCED OVER
PORTIONS OF THE LOWER DESERT). MUCH DRIER AIR OVERSPREADS THE ENTIRE
FORECAST AREA BY LATE WEDNESDAY...THEN PERSISTS THROUGH THE
REMAINDER OF THE WEEK. COULD SEE A BIT WARMER TEMPS BY NEXT WEEKEND
AS UPPER HIGH CENTERED OVER THE SOUTH-CENTRAL UNITED STATES
STRENGTHENS AND EXPANDS TOWARD THE WEST...HOWEVER...NUMERICAL MODELS
AGREE THAT MEAN LONG WAVE TROUGH POSITION WILL REMAIN OVER OR NEAR
THE WEST COAST FOR THE NEXT 7-10 DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
TYPICAL DIURNAL WINDS WITH FEW TO SCATTERED CLOUDS BETWEEN 10 AND 12
THOUSAND FEET THROUGH MONDAY.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKIES ARE EXPECTED THROUGH TUESDAY. WINDS GUSTING TO BETWEEN
20 AND 25 KNOTS ARE EXPECTED FROM THE SOUTH AT KBLH THIS AFTERNOON
AND EARLY THIS EVENING AND FROM THE WEST AT KIPL THIS EVENING.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS EAST OF GLOBE
WEDNESDAY. OTHERWISE...LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS
EXPECTED TO DEVELOP NEAR THE WEST COAST WITH COOLER WEATHER
WEDNESDAY. THIS SYSTEM IS ALSO EXPECTED TO RESULT IN BREEZY WEATHER
FROM THE SOUTHWEST WEDNESDAY AFTERNOON WITH GUSTS BETWEEN 20 AND 30
MPH. SOMEWHAT BELOW AVERAGE TEMPERATURES FOR EARLY SEPTEMBER AND DRY
AIR ARE EXPECTED THROUGH THE PERIOD WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ/DG
AVIATION...ELLIS
FIRE WEATHER...ELLIS
000
FXUS66 KMTR 051750
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1045 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 9:00 AM PDT SUNDAY...A STRONG NORTHERLY GRADIENT
HAS NEARLY WIPED THE COAST CLEAN OF STRATUS THIS MORNING. HOWEVER...
A FEW PATCHES STILL EXIST AS ONSHORE FLOW TO THE CENTRAL VALLEY
REMAINS AT A MODERATE LEVEL. THE RESIDUAL LOW CLOUDS WILL
DISSIPATE BY LATE MORNING REVEALING A SUNNY SKY. THE SUNNY SKY WILL
MELD INTO A CLEAR SKY OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
OVER IDAHO PRODUCING OFFSHORE FLOW. THE OFFSHORE FLOW WILL BE STRONG
ENOUGH TO KEEP THE MARINE LAYER MIXED UP AND LOW CLOUDS FROM
FORMING THROUGH MONDAY. ALSO...TONIGHT/S NORTHEASTERLY GRADIENT
WILL ALLOW MODERATE WINDS TO DEVELOP IN THE NORTH AND EAST BAY
MOUNTAINS ALONG WITH POOR HUMIDITY RECOVERIES. THEREFORE...HAVE
PLACED A HEADLINE IN THE FIRE WEATHER PLANNING FORECAST TO INCREASE
AWARENESS. SINCE THE OFFSHORE FLOW WILL BE SHORT LIVED...LATE TONIGHT
THROUGH MONDAY MORNING...AND THROUGH DISCUSSION WITH OTHER INTERESTED
PARTIES...HAVE DECIDED NOT TO ISSUE A RED FLAG WARNING.
ON MONDAY A TRANSITION WILL OCCUR AS A LOW PRESSURE TROUGH BEGINS
ITS SOUTHWARD PROGRESSION FROM THE GULF OF ALASKA. A COOLER
AIRMASS...SURFACE ONSHORE FLOW AND THE REDEVELOPMENT OF THE MARINE
LAYER WILL RETURN THE AREA TO WHAT HAS BECOME TYPICAL FOR THIS
SUMMER. THE TROUGH REMAINS OVERHEAD THROUGH THE WEEK AND EVEN INTO
NEXT WEEKEND.
&&
.AVIATION...AS OF 10:45 AM PDT SUNDAY...DEVELOPING OFFSHORE FLOW HAS
CLEARED STRATUS FROM SF BAY REGION. LINGERING LOW CLOUDS AROUND MRY
BAY TO CLEAR SHORTLY WITH LOOK OUT THE WINDOW REVEALING NO CIG AT
KMRY.
.VICINITY OF KSFO...VFR TODAY THROUGH MONDAY MORNING. NW WIND GUSTS
THIS AFTERNOON AND EVENING TO REMAIN UNDER 20 KT.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...LOW CIGS TO HAVE CLEARED BY 18Z FROM TAF
SITES. LOW CLOUD POOL IN MONTEREY BAY MAY BE TOUGH TO CLEAR OUT
WITH OFFSHORE WINDS RIDING ON TOP OF THE SHALLOW INVERSION. HOWEVER
EXPECT COMPLETE CLEARING EVEN AT KWVI TODAY. HAVE PUT TEMPO GROUPS
FOR SHALLOW MARINE LAYER WITH REDUCED CIGS TO RETURN LATE TONIGHT
INTO EARLY MONDAY MORNING. THIS IS MEDIUM CONFIDENCE AS OFFSHORE
FLOW MAY BE STRONG ENOUGH TO COMPLETELY SCOUR THINGS OUT AND GIVE
KMRY AND KSNS A VFR START LABOR DAY MORNING. WILL ASSESS TRENDS THIS
AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...GLW...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...SF BAY THIS AFTERNOON AND EVENING.
&&
$$
PUBLIC FORECAST: EVANS
AVIATION/MARINE: RWW
000
FXUS66 KMTR 051747
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1045 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 9:00 AM PDT SUNDAY...A STRONG NORTHERLY GRADIENT
HAS NEARLY WIPED THE COAST CLEAN OF STRATUS THIS MORNING. HOWEVER...
A FEW PATCHES STILL EXIST AS ONSHORE FLOW TO THE CENTRAL VALLEY
REMAINS AT A MODERATE LEVEL. THE RESIDUAL LOW CLOUDS WILL
DISSIPATE BY LATE MORNING REVEALING A SUNNY SKY. THE SUNNY SKY WILL
MELD INTO A CLEAR SKY OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
OVER IDAHO PRODUCING OFFSHORE FLOW. THE OFFSHORE FLOW WILL BE STRONG
ENOUGH TO KEEP THE MARINE LAYER MIXED UP AND LOW CLOUDS FROM
FORMING THROUGH MONDAY. ALSO...TONIGHT/S NORTHEASTERLY GRADIENT
WILL ALLOW MODERATE WINDS TO DEVELOP IN THE NORTH AND EAST BAY
MOUNTAINS ALONG WITH POOR HUMIDITY RECOVERIES. THEREFORE...HAVE
PLACED A HEADLINE IN THE FIRE WEATHER PLANNING FORECAST TO INCREASE
AWARENESS. SINCE THE OFFSHORE FLOW WILL BE SHORT LIVED...LATE TONIGHT
THROUGH MONDAY MORNING...AND THROUGH DISCUSSION WITH OTHER INTERESTED
PARTIES...HAVE DECIDED NOT TO ISSUE A RED FLAG WARNING.
ON MONDAY A TRANSITION WILL OCCUR AS A LOW PRESSURE TROUGH BEGINS
ITS SOUTHWARD PROGRESSION FROM THE GULF OF ALASKA. A COOLER
AIRMASS...SURFACE ONSHORE FLOW AND THE REDEVELOPMENT OF THE MARINE
LAYER WILL RETURN THE AREA TO WHAT HAS BECOME TYPICAL FOR THIS
SUMMER. THE TROUGH REMAINS OVERHEAD THROUGH THE WEEK AND EVEN INTO
NEXT WEEKEND.
&&
.AVIATION...AS OF 10:45 AM PDT SUNDAY...DEVELOPING OFFSHORE FLOW HAS
CLEARED STRATUS FROM SF BAY REGION. LINGERING LOW CLOUDS AROUND MRY
BAY TO CLEAR SHORTLY WITH LOOK OUT THE WINDOW REVEALING NO CIG AT
KMRY.
.VICINITY OF KSFO...VFR TODAY THROUGH MONDAY MORNING. NW WIND GUSTS
THIS AFTERNOON AND EVENING TO REMAIN UNDER 20 KT.
.KSFO BRIDGE APPROACH...VFR TODAY THROUGH MONDAY MORNING.
.MRY BAY AREA TERMINALS...LOW CIGS TO HAVE CLEARED BY 18Z FROM TAF
SITES. LOW CLOUD POOL IN MONTEREY BAY MAY BE TOUGH TO CLEAR OUT
WITH OFFSHORE WINDS RIDING ON TOP OF THE SHALLOW INVERSION. HOWEVER
EXPECT COMPLETE CLEARING EVEN AT KWVI TODAY. HAVE PUT TEMPO GROUPS
FOR SHALLOW MARINE LAYER WITH REDUCED CIGS TO RETURN LATE TONIGHT
INTO EARLY MONDAY MORNING. THIS IS MEDIUM CONFIDENCE AS OFFSHORE
FLOW MAY BE STRONG ENOUGH TO COMPLETELY SCOUR THINGS OUT AND GIVE
KMRY AND KSNS A VFR START LABOR DAY MORNING. WILL ASSESS TRENDS THIS
AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...SCA...ALL COASTAL WATERS EXCEPT PT REYES
TO PT PINOS 0-10 NM.
SCA...SF BAY THIS AFTERNOON AND EVENING.
&&
$$
PUBLIC FORECAST: EVANS
AVIATION/MARINE: RWW
000
FXUS66 KHNX 051651 CCA
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
951 AM PDT SUN SEP 5 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN AS A TROUGH OF LOW
PRESSURE BRUSHES THE REGION TODAY. THIS WILL BRING A SLIGHT COOLING
TREND THROUGH LABOR DAY. A STRONGER LOW PRESSURE SYSTEM WILL THEN
PROVIDE A MORE SIGNIFICANT COOLDOWN BY MIDWEEK AS IT PUSHES
THROUGH.
&&
.UPDATE...
CLEAR DRY CONDITIONS THIS MORNING. SATELLITE IMAGES SHOW SMOKE
FROM THE SHEEP WILDFIRE FLOWING ALONG THE KING RIVER IN THE SIERRA
INTO THE SAN JOAQUIN VALLEY. TEMPERATURE TRENDS ARE A BIT COOLER
AT MOST LOCALES EXCEPT TOWARDS MOJAVE AND BAKERSFIELD. PROFILERS
SHOW A WEAKER LOW LEVEL TEMPERATURE INVERSION WITH 1-2C DEGREES
COOLER ABOVE THE INVERSION. TEMPERATURES A BIT COOLER TODAY ACROSS
ENTIRE DISTRICT. NO UPDATES PLANNED THIS MORNING.
.DISCUSSION...
HIGH TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR YESTERDAY
AFTERNOON WERE MOSTLY DOWN AROUND A DEGREE OR SO FROM HIGHS
FRIDAY. THE SLIGHT COOLING TREND WILL CONTINUE THROUGH LABOR DAY
AS THE RIDGE OVERHEAD FURTHER WEAKENS IN RESPONSE TO A TROUGH
BRUSHING THE REGION AS IT TRACKS OUT OF THE PACIFIC NORTHWEST.
THIS WILL ALSO BRING SOME GUSTY WINDS OVER THE SIERRA RIDGES AND
THROUGH AND BELOW THE PASSES OF THE KERN COUNTY MOUNTAINS BUT
EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS. A MORE SIGNIFICANT
COOLDOWN WILL THEN BE IN STORE THROUGH MIDWEEK AS A FOLLOWING
TROUGH DIGS FARTHER SOUTH ALONG THE COAST AND SWINGS INLAND.
TEMPERATURES ARE EXPECTED TO DECREASE FROM AROUND CLIMO TUESDAY TO
AS MUCH AS 10-15 DEGREES LOWER FOR WEDNESDAY/THURSDAY. BREEZY
CONDITIONS WILL AGAIN DEVELOP AS THE SYSTEM MOVES THROUGH THE
REGION TUESDAY NIGHT/WEDNESDAY. SLIGHT CHANCES FOR PRECIPITATION
OVER THE SIERRA NORTH OF KINGS CANYON REMAIN IN THE FORECAST FOR
WEDNESDAY INTO THURSDAY AS THE SYSTEM PASSES...THOUGH THE MODELS
SHOW LIMITED AVAILABLE MOISTURE.TEMPERATURES ARE EXPECTED TO
RECOVER SLIGHTLY BY FRIDAY...BUT REMAINING GENERALLY BELOW
SEASONAL AVERAGES INTO EARLY NEXT WEEK AS ADDITIONAL SHORTWAVE
ENERGY DROPS SOUTH TOWARD THE REGION.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 18Z MONDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BINGHAM
SYNOPSIS...BSO
WEATHER.GOV/HANFORD
000
FXUS65 KPSR 051650
AFDPSR
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST SUN SEP 5 2010
.SYNOPSIS...
EXPECT ANOTHER HOT DAY TODAY AS HIGH PRESSURE ALOFT PERSISTS OVER
THE SOUTHWEST UNITED STATES. THE WEATHER PATTERN WILL CHANGE DURING
THE NEXT FEW DAYS...WITH LOW PRESSURE ALOFT BECOMING THE DOMINANT
WEATHER FEATURE OVER THE WESTERN UNITED STATES. CONSEQUENTLY...
TEMPERATURES WILL TREND DOWNWARD DURING MUCH OF THE UPCOMING
WEEK...WITH BELOW NORMAL READINGS LIKELY WEDNESDAY THROUGH FRIDAY.
THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL OCCUR OVER
SOUTH-CENTRAL ARIZONA MONDAY NIGHT THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
MORNING SOUNDINGS SHOW DRYING AT PSR AND TWC COMPARED TO
YESTERDAY...WITH MOISTENING AT FGZ. ALL OF THEM SHOW ADDITIONAL
WARMING ALOFT...GENERALLY BETWEEN 600 MB AND 450 MB. LATEST
RUC/NAM/GFS FORECAST SOUNDINGS SHOW CONDITIONS REMAINING TOO STABLE
TODAY FOR THUNDERSTORMS OVER OUR FORECAST AREA. THEY ALSO GO ON TO
SHOW MOISTENING TONIGHT AND MONDAY OVER SOUTH-CENTRAL ARIZONA ALONG
WITH A LITTLE BIT OF COOLING ALOFT. FORECAST SOUNDINGS ALSO INDICATE
MAX TEMPS WILL HAVE LITTLE CHANGE TODAY OVER SOUTH-CENTRAL ARIZONA
WITH SLIGHT COOLING OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.
NO UPDATES. MORE LATER.
PREVIOUS DISCUSSION...
HIGH PRESSURE ALOFT WILL BRING ABOVE NORMAL DAYTIME HIGHS AGAIN
TODAY...THOUGH FORECAST SOUNDINGS SUGGEST MAX TEMPS WILL BE A COUPLE
DEGREES LOWER THAN WHAT OCCURRED SATURDAY. UPPER AIR PATTERN WILL
UNDERGO A SIGNIFICANT CHANGE DURING THE NEXT FEW DAYS...AS LOW
PRESSURE ALOFT BECOMES THE DOMINANT WEATHER FEATURE OVER THE WESTERN
UNITED STATES WHILE THE SUBTROPICAL HIGH IS SUPPRESSED FAR TO OUR
SOUTH AND EAST. A RATHER STRONG LOW PRESSURE SYSTEM AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...AND BRING DRY AND COOLER AIR TO THE REGION. 12Z 850 MB
TEMPS FORECAST TO LOWER FROM 26C TODAY TO 17-18C BY THURSDAY/
FRIDAY...WHEN BELOW NORMAL MAX AND MIN TEMPS ARE A GOOD BET. THIS
WEATHER CHANGE HAS BEEN WELL-ADVERTISED FOR SEVERAL DAYS NOW.
PRECIPITATION CHANCES DURING THIS TRANSITION HAVE BEEN TOUGHER TO
DEAL WITH...AS NUMERICAL MODELS THE PAST FEW DAYS HAVE PROVIDED
WIDELY DIVERGENT SOLUTIONS REGARDING DEGREE OF MOIST ADVECTION AND
STRENGTH/TRACK OF A WEAK WEATHER DISTURBANCE EMANATING FROM THE
SUBTROPICS IN ADVANCE OF THE AFOREMENTIONED LOW PRESSURE SYSTEM/COLD
FRONT. NAM/ECMWF/GFS HAVE NOW CONVERGED ON WHAT APPEARS TO BE A
REASONABLE SOLUTION...WITH MOIST ADVECTION OCCURRING PRIMARILY OVER
SOUTH-CENTRAL AZ MONDAY AFTN INTO TUESDAY AS WEAK DISTURBANCE
APPROACHES FROM THE SOUTHWEST. AT THE SAME TIME...UPPER LEVEL JET
STREAK ASSOCIATED WITH THE STRONG LOW PRESSURE SYSTEM STRENGTHENS TO
OUR NORTH...WITH EASTERN HALF OF OUR FORECAST AREA UNDER RIGHT-REAR
QUAD. MODEST DEGREE OF CAPE EXISTS IN FORECAST SOUNDINGS BY TUESDAY
MORNING...SO THUNDERSTORM POTENTIAL SHOULD EXIST. INTRODUCED SLIGHT
CHANCE FOR SHOWERS/THUNDERSTORMS MAINLY OVER SOUTH-CENTRAL AZ MONDAY
NIGHT THROUGH TUESDAY EVENING (PRECIP CHANCES MAY BE TOO
CONSERVATIVE...BUT AT LEAST PRECIP CHANCE HAS BEEN INTRODUCED OVER
PORTIONS OF THE LOWER DESERT). MUCH DRIER AIR OVERSPREADS THE ENTIRE
FORECAST AREA BY LATE WEDNESDAY...THEN PERSISTS THROUGH THE
REMAINDER OF THE WEEK. COULD SEE A BIT WARMER TEMPS BY NEXT WEEKEND
AS UPPER HIGH CENTERED OVER THE SOUTH-CENTRAL UNITED STATES
STRENGTHENS AND EXPANDS TOWARD THE WEST...HOWEVER...NUMERICAL MODELS
AGREE THAT MEAN LONG WAVE TROUGH POSITION WILL REMAIN OVER OR NEAR
THE WEST COAST FOR THE NEXT 7-10 DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
A FAIRLY TYPICAL WEATHER PATTERN IS EXPECTED TODAY AS SOUTHEASTERLY
WINDS SWING TO THE WEST DURING THE AFTERNOON HOURS. WINDS WILL
EVENTUALLY BECOME SOUTHEASTERLY AGAIN DURING THE EARLY MORNING
HOURS. SOME INCREASE IN MID/HIGH CLOUDS EXPECTED THIS AFTERNOON.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKY THROUGH MONDAY MORNING. SOUTHERLY WINDS WILL GRADUALLY
DEVELOP THIS AFTERNOON THEN QUICKLY SWITCH TO SOUTHWEST/WEST IN THE
EARLY EVENING. STRONGER GUSTS EXPECTED FOR A FEW HOURS AT KIPL
DURING THIS SWITCH.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
MOISTURE AND PRECIPITATION CHANCES WILL INCREASE ACROSS EASTERN
ARIZONA TUESDAY AND WEDNESDAY WHILE DRIER AIR SPREADS ACROSS
SOUTHERN CALIFORNIA AND WESTERN ARIZONA AS A LARGE TROUGH DIGS INTO
THE REGION. WINDS WILL ALSO BE HEIGHTENED DURING THIS PERIOD. A
QUIETER WEATHER PATTERN WILL THEN SETTLE IN FOR THE REMAINDER OF THE
WEEK. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL WITH LOW AFTERNOON
HUMIDITY VALUES COUPLED WITH DECENT OVERNIGHT RECOVERY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ/DG
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
000
FXUS66 KHNX 051644
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
944 AM PDT SUN SEP 5 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN SUNDAY AS A TROUGH OF LOW
PRESSURE MOVES INTO THE REGION. THIS WILL BRING COOLER TEMPERATURES
TEMPERATURES FOR LABOR DAY AND THE FIRST PART OF NEXT WEEK.
&&
.UPDATE...
CLEAR DRY CONDITIONS THIS MORNING. SATELLITE IMAGES SHOW SMOKE
FROM THE SHEEP WILDFIRE FLOWING ALONG THE KING RIVER IN THE SIERRA
INTO THE SAN JOAQUIN VALLEY. TEMPERATURE TRENDS ARE A BIT COOLER
AT MOST LOCALES EXCEPT TOWARDS MOJAVE AND BAKERSFIELD. PROFILERS
SHOW A WEAKER LOW LEVEL TEMPERATURE INVERSION WITH 1-2C DEGREES
COOLER ABOVE THE INVERSION. TEMPERATURES A BIT COOLER TODAY ACROSS
ENTIRE DISTRICT. NO UPDATES PLANNED THIS MORNING.
.DISCUSSION...
HIGH TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR YESTERDAY
AFTERNOON WERE MOSTLY DOWN AROUND A DEGREE OR SO FROM HIGHS
FRIDAY. THE SLIGHT COOLING TREND WILL CONTINUE THROUGH LABOR DAY
AS THE RIDGE OVERHEAD FURTHER WEAKENS IN RESPONSE TO A TROUGH
BRUSHING THE REGION AS IT TRACKS OUT OF THE PACIFIC NORTHWEST.
THIS WILL ALSO BRING SOME GUSTY WINDS OVER THE SIERRA RIDGES AND
THROUGH AND BELOW THE PASSES OF THE KERN COUNTY MOUNTAINS BUT
EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS. A MORE SIGNIFICANT
COOLDOWN WILL THEN BE IN STORE THROUGH MIDWEEK AS A FOLLOWING
TROUGH DIGS FARTHER SOUTH ALONG THE COAST AND SWINGS INLAND.
TEMPERATURES ARE EXPECTED TO DECREASE FROM AROUND CLIMO TUESDAY TO
AS MUCH AS 10-15 DEGREES LOWER FOR WEDNESDAY/THURSDAY. BREEZY
CONDITIONS WILL AGAIN DEVELOP AS THE SYSTEM MOVES THROUGH THE
REGION TUESDAY NIGHT/WEDNESDAY. SLIGHT CHANCES FOR PRECIPITATION
OVER THE SIERRA NORTH OF KINGS CANYON REMAIN IN THE FORECAST FOR
WEDNESDAY INTO THURSDAY AS THE SYSTEM PASSES...THOUGH THE MODELS
SHOW LIMITED AVAILABLE MOISTURE.TEMPERATURES ARE EXPECTED TO
RECOVER SLIGHTLY BY FRIDAY...BUT REMAINING GENERALLY BELOW
SEASONAL AVERAGES INTO EARLY NEXT WEEK AS ADDITIONAL SHORTWAVE
ENERGY DROPS SOUTH TOWARD THE REGION.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 18Z MONDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BINGHAM
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KSTO 051626
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
925 AM PDT SUN SEP 5 2010
.DISCUSSION...
UPPER RIDGE CONTINUES TO FLATTEN AS AN UPPER TROUGH MOVES THROUGH
THE PACIFIC NORTHWEST. FLOW AT THE LOWER LEVELS HAS BECOME NORTHERLY
AND ALTHOUGH THE RDD-SAC HAS NOT INCREASED SIGNIFICANTLY...THE
MFR-RDD GRADIENT HAS NOW STRENGTHENED TO ABOVE 10 MB. TEMPERATURES
ACROSS THE FORECAST AREA ARE GENERALLY WITHIN A FEW DEGREES OF 24
HOURS AGO. IT IS WORTHWHILE TO NOTE HOWEVER THAT AREAS IN SOUTHERN
OREGON WHERE COOLER AIR HAS FILTERED IN ARE NOW RUNNING SEVERAL
DEGREES COOLER THAN YESTERDAY.
COOLER AIR WILL CONTINUE TO ADVECT INTO INTERIOR NORTHERN CALIFORNIA
AS THE DRY COLD FRONT MOVES THROUGH. THE NORTHERN ZONES SHOULD SEE
THE MOST COOLING TODAY...ON THE ORDER OF 5 TO 10 DEGREES COOLER THAN
YESTERDAY. TEMPS SHOULD DROP ONLY A FEW DEGREES ELSEWHERE. ENHANCED
SUBSIDENCE AND COLD AIR ADVECTION WILL BRING LOCALLY GUSTY WINDS
PARTICULARLY TOWARDS THE NORTHERN SAC VALLEY...WHERE WE COULD SEE
SUSTAINED 10 TO 20 MPH WINDS WITH LOCAL GUSTS UP TO AROUND 35 MPH.
LACK OF UPPER SUPPORT SHOULD KEEP WINDS BELOW ADVISORY LEVELS.
THE UPPER TROUGH SHIFTS EASTWARD TONIGHT AND THE SURFACE PRESSURE
GRADIENT WILL BECOME NORTHEASTERLY IN RESPONSE. WILL LIKELY SEE SOME
LOCALLY GUSTY CONDITIONS DOWN FAVORABLY ORIENTED SIERRA CANYONS
TONIGHT INTO EARLY MONDAY.
A BRIEF SHORTWAVE RIDGE WILL MOVE THROUGH LABOR DAY
MONDAY...BRINGING A FEW DEGREES OF ATMOSPHERIC WARMING TO SLIGHTLY
WARMER THAN AVERAGE LEVELS. TUESDAY WILL BRING COOLING OF A FEW
DEGREES FROM MONDAYS HIGHS AS A GULF OF ALASKA TROUGH BEGINS TO DIG
SOUTHWARD.
THE MORE SIGNIFICANT COOLING OCCURS ON WEDNESDAY AS THE UPPER TROUGH
CONTINUES TO AMPLIFY ALONG THE WEST COAST. HPC STANDARDIZED ANOMALY
CHARTS CONTINUE TO ADVERTISE THE 500MB HEIGHTS OF THIS SYSTEM AS 3
TO 4 DEVIATIONS LOWER THAN NORMAL. THIS WOULD PUT IT ALONG SIMILAR
LINES AS THE SYSTEM THAT MOVED THROUGH LAST WEEKEND THAT BROUGHT
LIGHT SHOWERS TO PARTS OF THE VALLEY AND MOUNTAINS. GIVEN THE
SIMILARITIES BETWEEN THE TWO SYSTEMS...WILL CONSIDER INCREASING
CHANCES OF PRECIPITATION WITH THE AFTERNOON PACKAGE.
SOME MODEL DIFFERENCES CROP UP BEYOND THIS POINT...BUT THE GENERAL
MESSAGE IS THAT COOLER THAN AVERAGE WEATHER IS EXPECTED FOR THE REST
OF THE WEEK. DANG
&&
.AVIATION...
VFR CONDITIONS WITH CLEAR SKIES EXPECTED FOR TODAY AND TONIGHT. MAIN
AVIATION ISSUE FOR TODAY WILL BE NORTHERLY WINDS INCREASING THROUGH
THE DAY. GUSTS THIS AFTERNOON OF 30 KT ARE POSSIBLE ACROSS THE
NORTHERN AND CENTRAL SACRAMENTO VALLEY...TO AROUND 20 KT AROUND THE
SACRAMENTO AND NORTHERN SAN JOAQUIN VALLEYS. THESE VALLEY WINDS WILL
GRADUALLY DECREASE SUNDAY NIGHT WITH NORTHEASTERLY WINDS IN THE
MOUNTAINS INCREASING THROUGH FAVORED CANYONS AND PASSES.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS66 KMTR 051622
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
920 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 9:00 AM PDT SUNDAY...A STRONG NORTHERLY GRADIENT
HAS NEARLY WIPED THE COAST CLEAN OF STRATUS THIS MORNING. HOWEVER...
A FEW PATCHES STILL EXIST AS ONSHORE FLOW TO THE CENTRAL VALLEY
REMAINS AT A MODERATE LEVEL. THE RESIDUAL LOW CLOUDS WILL
DISSIPATE BY LATE MORNING REVEALING A SUNNY SKY. THE SUNNY SKY WILL
MELD INTO A CLEAR SKY OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
OVER IDAHO PRODUCING OFFSHORE FLOW. THE OFFSHORE FLOW WILL BE STRONG
ENOUGH TO KEEP THE MARINE LAYER MIXED UP AND LOW CLOUDS FROM
FORMING THROUGH MONDAY. ALSO...TONIGHT/S NORTHEASTERLY GRADIENT
WILL ALLOW MODERATE WINDS TO DEVELOP IN THE NORTH AND EAST BAY
MOUNTAINS ALONG WITH POOR HUMIDITY RECOVERIES. THEREFORE...HAVE
PLACED A HEADLINE IN THE FIRE WEATHER PLANNING FORECAST TO INCREASE
AWARENESS. SINCE THE OFFSHORE FLOW WILL BE SHORT LIVED...LATE TONIGHT
THROUGH MONDAY MORNING...AND THROUGH DISCUSSION WITH OTHER INTERESTED
PARTIES...HAVE DECIDED NOT TO ISSUE A RED FLAG WARNING.
ON MONDAY A TRANSITION WILL OCCUR AS A LOW PRESSURE TROUGH BEGINS
ITS SOUTHWARD PROGRESSION FROM THE GULF OF ALASKA. A COOLER
AIRMASS...SURFACE ONSHORE FLOW AND THE REDEVELOPMENT OF THE MARINE
LAYER WILL RETURN THE AREA TO WHAT HAS BECOME TYPICAL FOR THIS
SUMMER. THE TROUGH REMAINS OVERHEAD THROUGH THE WEEK AND EVEN INTO
NEXT WEEKEND.
&&
.AVIATION...AS OF 6:45 AM PDT SUNDAY...STRONG NORTHERLY GRADIENT
HAS KEPT THE STRATUS PATCHY IN THE SFO BAY AREA AND INTO THE
MRY BAY AREA.
.VICINITY OF KSFO...VFR CONDITIONS EXPECTED.
.KSFO BRIDGE APPROACH...PATCHY CLOUDS OVER THE COASTAL AND EAST
BAY HILLS MAY BRIEFLY MOVE OVER THE APPROACH WITH SCT-BKN CONDITIONS
THROUGH 17Z.
.MRY BAY AREA TERMINALS...IFR CIGS FOR LOW CIGS AND VSBYS. VSBYS
IMPROVING TO 5 MILES OR GREATER AFTER 16Z WITH CIGS CLEARING
AFTER 18-19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: EVANS
AVIATION/MARINE: W PI
000
FXUS66 KSGX 051601
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
900 AM PDT SUN SEP 5 2010
.SYNOPSIS...
A COOLING TREND BEGINS TODAY AND CONTINUES THROUGH THURSDAY WITH A
DEEPER MARINE LAYER FOR MORE EXTENSIVE NIGHT AND MORNING COASTAL LOW
CLOUDS AND FOG. LOCALLY WINDY AT TIMES IN THE MOUNTAINS AND DESERTS.
A LITTLE WARMER FOR FRIDAY THROUGH NEXT WEEKEND UNDER WEAKER LOW
PRESSURE.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THIS MORNING...THE MARINE LAYER REMAINS SHALLOW WITH AREAS OF LOW
CLOUDS AND LOCALLY DENSE FOG EXTENDING LOCALLY INLAND...INTO THE
WESTERNMOST VALLEYS OF SAN DIEGO COUNTY. THE CLOUDS AND FOG WILL
CLEAR BACK TO NEAR THE BEACHES FOR THE AFTERNOON...WITH SOME CLOUDS
AND FOG REMAINING AT SOME BEACHES.
A TROUGH OF LOW PRESSURE MOVING INLAND THROUGH THE PACIFIC NORTHWEST
WILL INCREASE THE ONSHORE FLOW IN SOUTHWEST CALIFORNIA TODAY
BRINGING A FEW DEGREES OF COOLING FOR MOST AREAS...WITH THE MOST
COOLING IN SOME VALLEY AND INLAND COASTAL AREAS. THE STRONGER
ONSHORE FLOW WILL BRING GUSTY WEST WINDS TO THE MOUNTAINS AND
DESERTS FOR LATE AFTERNOON THROUGH LATE EVENING.
FOR MONDAY...CONTINUED SLOW COOLING AND DEEPENING OF THE MARINE
LAYER UNDER WEAK LOW PRESSURE.
FOR TUESDAY THROUGH THURSDAY...ANOTHER TROUGH OF LOW PRESSURE WILL
DEEPEN ALONG THE WEST COAST...LOWERING TEMPERATURES TO WELL BELOW
SEASONAL AVERAGES...DEEPENING THE MARINE LAYER FOR MORE EXTENSIVE
NIGHT AND MORNING LOW CLOUDS. INCREASING ONSHORE PRESSURE WILL
PRODUCE GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS AT
TIMES...MAINLY ON THURSDAY.
FOR FRIDAY THROUGH NEXT WEEKEND...SLOW WARMING UNDER WEAKER LOW
PRESSURE.
&&
.AVIATION...
051500Z...MARINE LAYER ABOUT 1100 FT. BASES AROUND 500 TO 700 FT
MSL. AREAS OF VSBY 1/2SM OR LESS THIS MORNING AND EXPECT STRATUS/FOG
TO CLEAR TO THE COAST 16-17Z. STRATUS AND FOG EXPECTED TO REMAIN
ALONG THE COAST THROUGH AFTERNOON. COASTAL EDDY FORECAST TO DEVELOP
TONIGHT WITH THE MARINE LAYER INCREASING TO ABOUT 2K FT OR HIGHER
WITH BASES AROUND 1K FT OR HIGHER. DENSE FOG INTO THE INLAND VALLEYS
LATE TONIGHT AND MONDAY MORNING. STRATUS/FOG EXPECTED TO MOVE BACK
INTO THE COASTAL AIRPORTS ABOUT 07-08Z.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...PG
AVIATION/MARINE...WHITLOW
NWS ON THE WEB AT WEATHER.GOV/SANDIEGO
000
FXUS66 KMTR 051354
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
206 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 2:06 AM PDT SUNDAY...A ROBUST NORTH-TO-SOUTH
FLOW HAS SCOURED LOW CLOUDS FROM THE COAST FROM NORTHERN SANTA CRUZ
COUNTY NORTHWARD. SATELLITE IMAGERY SHOWS STRATUS IN A STRAIGHT LINE
FROM SANTA CRUZ COUNTY SOUTHWARD TO WEST OF POINT CONCEPTION..AS
WELL AS INTO THE ENTIRE SALINAS VALLEY...WITH CLEAR SKIES ELSEWHERE.
LAST HOUR SURFACE PRESSURE GRADIENTS WERE 5.9 MB FROM ARCATA TO
SFO...7.1 MB FROM SFO TO LAS...AND 3.0 MB FROM SFO TO SAC.
STRONG NORTHERLY FLOW AS HIGH PRESSURE BRIEFLY BUILDS OFFSHORE WILL
PROVIDE A BIT OF A WARMING TREND FOR TODAY ACROSS THE DISTRICT WITH
TEMPERATURES WARMING TO THE 60S AND 70S AT THE COAST...TO THE 80S AND
90S INLAND...WITH SOME OF THE WARMEST INTERIOR AREAS EXCEEDING 100
DEGREES. LATE TONIGHT AN OFFSHORE FLOW IS FORECAST TO DEVELOP WITH
BREEZES PICKING UP ACROSS THE NORTH BAY HILLS. THE LATEST NAM KEEPS
WIND SPEEDS AT OR BELOW 35 KNOTS AT 925 MB...ERGO WIND ADVISORIES ARE
NOT ANTICIPATED BEING NECESSARY. WARMER CONDITIONS ARE THEN EXPECTED
ACROSS THE DISTRICT ON MONDAY. HOWEVER BY TUESDAY...A SHARP COOLING
TREND IS EXPECTED AS A DEEP TROUGH OF LOW PRESSURE DROPS SOUTHWARD
INTO NORTHERN CALIFORNIA FROM THE GULF OF ALASKA. THIS TROUGH IS THEN
PROGGED TO REMAIN ALONG THE WEST COAST FOR THE REMAINDER OF THE
FORECAST PERIOD KEEPING TEMPERATURES ON THE COOL SIDE WITH EPISODES
OF NIGHT AND MORNING LOW CLOUDS...FOG AND DRIZZLE ALONG THE COAST.
&&
.AVIATION...AS OF 6:45 AM PDT SUNDAY...STRONG NORTHERLY GRADIENT
HAS KEPT THE STRATUS PATCHY IN THE SFO BAY AREA AND INTO THE
MRY BAY AREA.
.VICINITY OF KSFO...VFR CONDITIONS EXPECTED.
.KSFO BRIDGE APPROACH...PATCHY CLOUDS OVER THE COASTAL AND EAST
BAY HILLS MAY BRIEFLY MOVE OVER THE APPROACH WITH SCT-BKN CONDITIONS
THROUGH 17Z.
.MRY BAY AREA TERMINALS...IFR CIGS FOR LOW CIGS AND VSBYS. VSBYS
IMPROVING TO 5 MILES OR GREATER AFTER 16Z WITH CIGS CLEARING
AFTER 18-19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: SSA
AVIATION/MARINE: W PI
000
FXUS66 KMTR 051318
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
206 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 2:06 AM PDT SUNDAY...A ROBUST NORTH-TO-SOUTH
FLOW HAS SCOURED LOW CLOUDS FROM THE COAST FROM NORTHERN SANTA CRUZ
COUNTY NORTHWARD. SATELLITE IMAGERY SHOWS STRATUS IN A STRAIGHT LINE
FROM SANTA CRUZ COUNTY SOUTHWARD TO WEST OF POINT CONCEPTION..AS
WELL AS INTO THE ENTIRE SALINAS VALLEY...WITH CLEAR SKIES ELSEWHERE.
LAST HOUR SURFACE PRESSURE GRADIENTS WERE 5.9 MB FROM ARCATA TO
SFO...7.1 MB FROM SFO TO LAS...AND 3.0 MB FROM SFO TO SAC.
STRONG NORTHERLY FLOW AS HIGH PRESSURE BRIEFLY BUILDS OFFSHORE WILL
PROVIDE A BIT OF A WARMING TREND FOR TODAY ACROSS THE DISTRICT WITH
TEMPERATURES WARMING TO THE 60S AND 70S AT THE COAST...TO THE 80S AND
90S INLAND...WITH SOME OF THE WARMEST INTERIOR AREAS EXCEEDING 100
DEGREES. LATE TONIGHT AN OFFSHORE FLOW IS FORECAST TO DEVELOP WITH
BREEZES PICKING UP ACROSS THE NORTH BAY HILLS. THE LATEST NAM KEEPS
WIND SPEEDS AT OR BELOW 35 KNOTS AT 925 MB...ERGO WIND ADVISORIES ARE
NOT ANTICIPATED BEING NECESSARY. WARMER CONDITIONS ARE THEN EXPECTED
ACROSS THE DISTRICT ON MONDAY. HOWEVER BY TUESDAY...A SHARP COOLING
TREND IS EXPECTED AS A DEEP TROUGH OF LOW PRESSURE DROPS SOUTHWARD
INTO NORTHERN CALIFORNIA FROM THE GULF OF ALASKA. THIS TROUGH IS THEN
PROGGED TO REMAIN ALONG THE WEST COAST FOR THE REMAINDER OF THE
FORECAST PERIOD KEEPING TEMPERATURES ON THE COOL SIDE WITH EPISODES
OF NIGHT AND MORNING LOW CLOUDS...FOG AND DRIZZLE ALONG THE COAST.
&&
.AVIATION...AS OF 6:00 AM PDT SUNDAY...STRONG NORTHERLY GRADIENT
HAS SWEPT THE STRATUS OUT OF THE SFO BAY AREA AND INTO THE MRY BAY
AREA.
.VICINITY OF KSFO...VFR CONDITIONS.
.KSFO BRIDGE APPROACH...VFR CONDITINS.
.MRY BAY AREA TERMINALS...IFR CIGS FOR LOW CIGS AND VSBYS. VSBYS
IMPROVING TO 5 MILES OR GREATER AFTER 16Z WITH CIGS CLEARING
AFTER 18-19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: SSA
AVIATION/MARINE: W PI
000
FXUS66 KLOX 051245
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
445 AM PDT SUN SEP 5 2010
NEW AVIATION DISCUSSION
.SYNOPSIS...
AN UPPER LOW MOVING INTO THE WEST COAST WILL BRING SOME COOLING TO
THE AREA TODAY. AS LOW PRESSURE STRENGTHENS OVER THE WEST...THE
COOLING TREND WILL CONTINUE THROUGH WEDNESDAY. THERE WILL BE AN
INCREASE IN NIGHT THROUGH MORNING LOW CLOUDS AND FOG IN COASTAL
AND VALLEY AREAS...WITH CLOUDS POSSIBLY REACHING THE COASTAL SLOPES
BY MID WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-TUE)...WDSPRD LOW CLOUDS AND FOG ON THE CENTRAL
COAST COAST THIS MORNING...AND CLOUDS HAVE BEGUN TO PUSH INTO THE
SANTA YNEZ VALLEY. CLOUDS WILL LIKELY PUSH INTO THE SALINAS VALLEY
AS WELL. ACROSS THE COASTAL WATERS...THERE HAS BEEN A RAPID
EXPANSION OF LOW CLOUDS ACROSS THE SANTA MONICA BASIN...AND CLOUDS
SHOULD HAVE NO TROUBLE PUSHING INTO CSTL SXNS OF L.A. AND VTU
COUNTIES. OFFSHORE N-S GRADS ACROSS SBA COUNTY MAY HOLD OFF STRATUS
FOR A WHILE...BUT EXPECT AT LEAST PATCHY COVERAGE NEAR THE COAST BY
DAYBREAK. MARINE LAYER HAS DEEPENED TO ABOUT 800 FEET OR SO...BUT
SHOULD STILL BE SHALLOW ENOUGH FOR SOME PATCHY DENSE FOG EARLY THIS
MORNING. PROFILER DATA SHOWS 4-6 DEGREES C OF COOLING BELOW 1000
FEET...WITH ABOUT 2-3 DEGREES C ABOVE THAT. ONSHORE GRADS BETWEEN
LAX AND DAG WERE A LITTLE MORE THAN 1 MB MORE ONSHORE THAN SAT AT
THIS TIME. ALL OF THESE FACTORS COMBINED SHOULD BRING NOTICEABLE
COOLING TO MUCH OF THE REGION TODAY...WITH TEMPS DOWN MOST
SIGNIFICANTLY ACROSS INLAND SECTIONS OF THE CSTL PLAIN AND IN THE
LOWER VALLEYS. STILL...EXPECT THE HOTTER INTERIOR VALLEY LOCATIONS
TO RISE WELL INTO THE 90S TODAY. THERE SHOULD BE A BIT LESS IN THE
WAY OF COOLING IN THE MTNS AND DESERTS TODAY. AND...NEAR THE
COAST...NOT MUCH CHANGE IS EXPECTED FROM THE CONTD VERY COOL
CONDITIONS THAT HAS BEEN PERVASIVE THIS SUMMER.
HEIGHTS/THICKNESSES WILL CONT TO LOWER ACROSS THE AREA TONIGHT AND
MONDAY AS A WEAK SHORT WAVE TROUGH DROPS THROUGH CA. N-S GRADS
SHOULD BE SHARP ENOUGH TO PRODUCE SOME GUSTY WINDS THROUGH AND BELOW
PASSES AND CANYONS OF THE SANTA YNEZ RANGE IN SRN SBA COUNTY AND
POSSIBLY THROUGH THE INTERSTATE 5 CORRIDOR TONIGHT. STRONG NWLY FLOW
ACROSS THE OUTER WATERS SHOULD CAUSE A DECENT EDDY TO SPIN UP...AND
THIS HAS BEEN ADVERTISED BY THE WRF FOR THE LAST COUPLE OF DAYS.
EXPECT WDSPRD LOW CLOUDS IN CSTL AREAS TONIGHT...AND THE EDDY SHOULD
HELP THE MARINE LAYER DEEPEN ENOUGH TO SEND CLOUDS INTO AT PORTIONS
OF THE L.A. AND VTU COUNTY VALLEYS TONIGHT. WITH THE NLY
GRADS...CLOUDS MAY HAVE A TOUGH TIME REACHING SRN SBA COUNTY...BUT
BELIEVE THEY WILL DO SO LATE AT NIGHT AFTER ANY GUSTY WINDS
DIMINISH. TEMPS WILL BE DOWN SIGNIFICANTLY IN MOST AREAS ON
MONDAY...WITH ANOTHER 5 TO 10 DEGREES OFF MAX TEMPS IN MOST AREAS.
THE EXCEPTION AGAIN WILL BE NEAR THE CST WHERE WARMING OVER THE PAST
FEW DAYS HAS BEEN MINIMAL.
THE WEAK TROUGH OVER THE AREA MON NIGHT AND TUE WILL BE KICKED
EASTWARD AS ANOTHER STRONGER TROUGH DIGS INTO THE PAC NW. THE MARINE
LAYER SHOULD DEEPEN...WITH NIGHT/MORNING LOW CLOUDS AND FOG IN ALL
CSTL AND MOST VALLEY AREAS. THERE WILL BE SEVERAL MORE DEGREES OF
COOLING IN MOST AREAS ON TUE...WITH TEMPS GENERALLY DOWN TO WELL
BELOW NORMAL LEVELS.
.LONG TERM (WED-SAT)...A STRONG UPPER LOW IS FCST TO DEVELOP OVER
THE PAC NW WED WITH A TROUGH EXTENDING SWD INTO SRN CA...THEN
THIS TROUGH AXIS SHOULD SWING THE E OF THE REGION ON THU. MARINE
LAYER SHOULD DEEPEN SUCH THAT LOW CLDS SHOULD REACH THE CSTL SLOPES
TUE NIGHT/WED MORNING...AND THERE WILL PROBABLY BE SOME DRIZZLE. WED
COULD BE A PARTIAL CLEARING TYPE OF DAY W OF THE MTNS...AND IT WILL
BE A VERY COOL DAY ACROSS THE REGION. THERE MAY BE ENOUGH COOLING
TO WIPE OUT THE MARINE LAYER WED NIGHT/THU...BUT FOR NOW...WILL KEEP
THE THEME OF WDSPRD NIGHT THRU MORNING CLOUDS/FOG. HEIGHTS WILL
BEGIN TO REBOUND A BIT FOR FRI AND SAT...BUT A BROAD TROUGH WILL
PERSIST...SO EXPECT TEMPS TO REMAIN BELOW NORMAL INTO SAT.
&&
.AVIATION...
05/1135Z
900 FOOT MARINE LAYER WILL BRING LIFR CONDS TO MOST COASTAL TAF
SITES THIS MORNING. KLGB COULD GO EITHER WAY BUT HAS A SLIGHTLY
BETTER CHC OF STAYING CLEAR. INVERSION IS STILL STRONG AND THERE IS
A CHC THAT CIGS WILL LINGER INTO THE EARLY AFTERNOON. THERE WILL BE
AN EARLIER RETURN OF CIGS THIS EVENING.
.KLAX...ONLY FAIR CONFIDENCE IN TAF WITH A 30 PERCENT CHC OF IFR
CIGS LASTING UNTIL 20Z OR 21Z.
.KBUR...VERY GOOD CONFIDENCE IN CAVU TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...BRUNO
AVIATION...RORKE
SYNOPSIS...DB
WWW.WEATHER.GOV/LOSANGELES
000
FXUS65 KPSR 051205 AAA
AFDPSR
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PHOENIX AZ
505 AM MST SUN SEP 5 2010
.UPDATE...UPDATED AVIATION AND FIRE WEATHER SECTIONS.
&&
.SYNOPSIS...
EXPECT ANOTHER HOT DAY TODAY AS HIGH PRESSURE ALOFT PERSISTS OVER
THE SOUTHWEST UNITED STATES. THE WEATHER PATTERN WILL CHANGE DURING
THE NEXT FEW DAYS...WITH LOW PRESSURE ALOFT BECOMING THE DOMINANT
WEATHER FEATURE OVER THE WESTERN UNITED STATES. CONSEQUENTLY...
TEMPERATURES WILL TREND DOWNWARD DURING MUCH OF THE UPCOMING
WEEK...WITH BELOW NORMAL READINGS LIKELY WEDNESDAY THROUGH FRIDAY.
THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL OCCUR OVER
SOUTH-CENTRAL ARIZONA MONDAY NIGHT THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
HIGH PRESSURE ALOFT WILL BRING ABOVE NORMAL DAYTIME HIGHS AGAIN
TODAY...THOUGH FORECAST SOUNDINGS SUGGEST MAX TEMPS WILL BE A COUPLE
DEGREES LOWER THAN WHAT OCCURRED SATURDAY. UPPER AIR PATTERN WILL
UNDERGO A SIGNIFICANT CHANGE DURING THE NEXT FEW DAYS...AS LOW
PRESSURE ALOFT BECOMES THE DOMINANT WEATHER FEATURE OVER THE WESTERN
UNITED STATES WHILE THE SUBTROPICAL HIGH IS SUPPRESSED FAR TO OUR
SOUTH AND EAST. A RATHER STRONG LOW PRESSURE SYSTEM AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...AND BRING DRY AND COOLER AIR TO THE REGION. 12Z 850 MB
TEMPS FORECAST TO LOWER FROM 26C TODAY TO 17-18C BY THURSDAY/
FRIDAY...WHEN BELOW NORMAL MAX AND MIN TEMPS ARE A GOOD BET. THIS
WEATHER CHANGE HAS BEEN WELL-ADVERTISED FOR SEVERAL DAYS NOW.
PRECIPITATION CHANCES DURING THIS TRANSITION HAVE BEEN TOUGHER TO
DEAL WITH...AS NUMERICAL MODELS THE PAST FEW DAYS HAVE PROVIDED
WIDELY DIVERGENT SOLUTIONS REGARDING DEGREE OF MOIST ADVECTION AND
STRENGTH/TRACK OF A WEAK WEATHER DISTURBANCE EMANATING FROM THE
SUBTROPICS IN ADVANCE OF THE AFOREMENTIONED LOW PRESSURE SYSTEM/COLD
FRONT. NAM/ECMWF/GFS HAVE NOW CONVERGED ON WHAT APPEARS TO BE A
REASONABLE SOLUTION...WITH MOIST ADVECTION OCCURRING PRIMARILY OVER
SOUTH-CENTRAL AZ MONDAY AFTN INTO TUESDAY AS WEAK DISTURBANCE
APPROACHES FROM THE SOUTHWEST. AT THE SAME TIME...UPPER LEVEL JET
STREAK ASSOCIATED WITH THE STRONG LOW PRESSURE SYSTEM STRENGTHENS TO
OUR NORTH...WITH EASTERN HALF OF OUR FORECAST AREA UNDER RIGHT-REAR
QUAD. MODEST DEGREE OF CAPE EXISTS IN FORECAST SOUNDINGS BY TUESDAY
MORNING...SO THUNDERSTORM POTENTIAL SHOULD EXIST. INTRODUCED SLIGHT
CHANCE FOR SHOWERS/THUNDERSTORMS MAINLY OVER SOUTH-CENTRAL AZ MONDAY
NIGHT THROUGH TUESDAY EVENING (PRECIP CHANCES MAY BE TOO
CONSERVATIVE...BUT AT LEAST PRECIP CHANCE HAS BEEN INTRODUCED OVER
PORTIONS OF THE LOWER DESERT). MUCH DRIER AIR OVERSPREADS THE ENTIRE
FORECAST AREA BY LATE WEDNESDAY...THEN PERSISTS THROUGH THE
REMAINDER OF THE WEEK. COULD SEE A BIT WARMER TEMPS BY NEXT WEEKEND
AS UPPER HIGH CENTERED OVER THE SOUTH-CENTRAL UNITED STATES
STRENGTHENS AND EXPANDS TOWARD THE WEST...HOWEVER...NUMERICAL MODELS
AGREE THAT MEAN LONG WAVE TROUGH POSITION WILL REMAIN OVER OR NEAR
THE WEST COAST FOR THE NEXT 7-10 DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
A FAIRLY TYPICAL WEATHER PATTERN IS EXPECTED TODAY AS SOUTHEASTERLY
WINDS SWING TO THE WEST DURING THE AFTERNOON HOURS. WINDS WILL
EVENTUALLY BECOME SOUTHEASTERLY AGAIN DURING THE EARLY MORNING
HOURS. SOME INCREASE IN MID/HIGH CLOUDS EXPECTED THIS AFTERNOON.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKY THROUGH MONDAY MORNING. SOUTHERLY WINDS WILL GRADUALLY
DEVELOP THIS AFTERNOON THEN QUICKLY SWITCH TO SOUTHWEST/WEST IN THE
EARLY EVENING. STRONGER GUSTS EXPECTED FOR A FEW HOURS AT KIPL
DURING THIS SWITCH.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
MOISTURE AND PRECIPITATION CHANCES WILL INCREASE ACROSS EASTERN
ARIZONA TUESDAY AND WEDNESDAY WHILE DRIER AIR SPREADS ACROSS
SOUTHERN CALIFORNIA AND WESTERN ARIZONA AS A LARGE TROUGH DIGS INTO
THE REGION. WINDS WILL ALSO BE HEIGHTENED DURING THIS PERIOD. A
QUIETER WEATHER PATTERN WILL THEN SETTLE IN FOR THE REMAINDER OF THE
WEEK. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL WITH LOW AFTERNOON
HUMIDITY VALUES COUPLED WITH DECENT OVERNIGHT RECOVERY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...DG
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
000
FXUS66 KLOX 051144
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
445 AM PDT SUN SEP 5 2010
NEW AVIATION DISCUSSION
.SYNOPSIS...
AN UPPER LOW MOVING INTO THE WEST COAST WILL BRING SOME COOLING TO
THE AREA TODAY. AS LOW PRESSURE STRENGTHENS OVER THE WEST...THE
COOLING TREND WILL CONTINUE THROUGH WEDNESDAY. THERE WILL BE AN
INCREASE IN NIGHT THROUGH MORNING LOW CLOUDS AND FOG IN COASTAL
AND VALLEY AREAS...WITH CLOUDS POSSIBLY REACHING THE COASTAL SLOPES
BY MID WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-TUE)...WDSPRD LOW CLOUDS AND ON THE CENTRAL COAST
COAST THIS MORNING...AND CLOUDS HAVE BEGUN TO PUSH INTO THE SANTA
YNEZ VALLEY. CLOUDS WILL LIKELY PUSH INTO THE SALINAS VALLEY AS
WELL. ACROSS THE COASTAL WATERS...THERE HAS BEEN A RAPID EXPANSION
OF LOW CLOUDS ACROSS THE SANTA MONICA BASIN...AND CLOUDS SHOULD HAVE
NO TROUBLE PUSHING INTO CSTL SXNS OF L.A. AND VTU COUNTIES. OFFSHORE
N-S GRADS ACROSS SBA COUNTY MAY HOLD OFF STRATUS FOR A WHILE...BUT
EXPECT AT LEAST PATCHY COVERAGE NEAR THE COAST BY DAYBREAK. MARINE
LAYER HAS DEEPENED TO ABOUT 800 FEET OR SO...BUT SHOULD STILL BE
SHALLOW ENOUGH FOR SOME PATCHY DENSE FOG EARLY THIS MORNING. PROFILER
DATA SHOWS 4-6 DEGREES C OF COOLING BELOW 1000 FEET...WITH ABOUT 2-3
DEGREES C ABOVE THAT. ONSHORE GRADS BETWEEN LAX AND DAG WERE A
LITTLE MORE THAN 1 MB MORE ONSHORE THAN SAT AT THIS TIME. ALL OF
THERE FACTORS COMBINED SHOULD BRING NOTICEABLE COOLING TO MUCH OF
THE REGION TODAY...WITH TEMPS DOWN MOST SIGNIFICANTLY ACROSS INLAND
SECTIONS OF THE CSTL PLAIN AND IN THE LOWER VALLEYS. STILL...EXPECT
THE HOTTER MORE INTERIOR VALLEY LOCATIONS TO RISE WELL INTO THE
90S TODAY. THERE SHOULD BE A BIT LESS IN THE WAY OF COOLING IN THE
MTNS AND DESERTS TODAY. AND...NEAR THE COAST...NOT MUCH CHANGE IS
EXPECTED FROM THE CONTD VERY COOL CONDITIONS THAT HAS BEEN PERVASIVE
THIS SUMMER.
HEIGHTS WILL CONT TO LOWER ACROSS THE AREA TONIGHT AND MONDAY AS A
WEAK SHORT WAVE TROUGH DROPS THROUGH CA. N-S GRADS SHOULD BE SHARP
ENOUGH TO PRODUCE SOME GUSTY WINDS THROUGH AND BELOW PASSES AND
CANYONS OF THE SANTA YNEZ RANGE IN SRN SBA COUNTY AND POSSIBLY
THROUGH THE INTERSTATE 5 CORRIDOR TONIGHT. STRONG NWLY FLOW ACROSS
THE OUTER WATERS SHOULD CAUSE A DECENT EDDY TO SPIN UP...AND THIS
HAS BEEN ADVERTISED BY THE WRF FOR THE LAST COUPLE OF DAYS. EXPECT
WDSPRD LOW CLOUDS IN CSTL AREAS TONIGHT...AND THE EDDY SHOULD HELP
THE MARINE LAYER DEEPEN ENOUGH TO SEND CLOUDS INTO AT PORTIONS OF
THE L.A. AND VTU COUNTY VALLEYS TONIGHT. WITH THE NLY GRADS...CLOUDS
MAY HAVE A TOUGH TIME REACHING SRN SBA COUNTY...BUT BELIEVE THEY
WILL DO SO LATE AT NIGHT AFTER ANY GUSTY WINDS DIMINISH. TEMPS WILL
BE DOWN SIGNIFICANTLY IN MOST AREAS ON MONDAY...WITH ANOTHER 5 TO 10
DEGREES OFF MAX TEMPS IN MOST AREAS. THE EXCEPTION AGAIN WILL BE
NEAR THE CST WHERE WARMING OVER THE PAST FEW DAYS HAS BEEN MINIMAL.
THE WEAK TROUGH OVER THE AREA MON NIGHT AND TUE WILL BE KICKED
EASTWARD AS ANOTHER STRONGER TROUGH DIGS INTO THE PAC NW. THE MARINE
LAYER SHOULD DEEPEN...WITH NIGHT/MORNING LOW CLOUDS AND FOG IN ALL
CSTL AND MOST VALLEY AREAS. THERE WILL BE SEVERAL MORE DEGREES OF
COOLING IN MOST AREAS ON TUE...WITH TEMPS GENERALLY DOWN TO WELL
BELOW NORMAL LEVELS.
.LONG TERM (WED-SAT)...A STRONG UPPER LOW IS FCST TO DEVELOP OVER
THE PAC NW WED WITH A TROUGH EXTENDING SWD INTO SRN CA...THEN
THIS TROUGH AXIS SHOULD SWING THE E OF THE REGION ON THU. MARINE
LAYER SHOULD DEEPEN SUCH THAT LOW CLDS SHOULD REACH THE CSTL SLOPES
TUE NIGHT/WED MORNING...AND THERE WILL PROBABLY BE SOME DRIZZLE. WED
COULD BE A PARTIAL CLEARING TYPE OF DAY W OF THE MTNS...AND IT WILL
BE A VERY COOL DAY ACROSS THE REGION. THERE MAY BE ENOUGH COOLING
TO WIPE OUT THE MARINE LAYER WED NIGHT/THU...BUT FOR NOW...WILL KEEP
THE THEME OF WDSPRD NIGHT THRU MORNING CLOUDS/FOG. HEIGHTS WILL
BEGIN TO REBOUND A BIT FOR FRI AND SAT...BUT A BROAD TROUGH WILL
PERSIST...SO EXPECT TEMPS TO REMAIN BELOW NORMAL INTO SAT.
&&
.AVIATION...
05/1135Z
900 FOOT MARINE LAYER WILL BRING LIFR CONDS TO MOST COASTAL TAF
SITES THIS MORNING. KLGB COULD GO EITHER WAY BUT HAS A SLIGHTLY
BETTER CHC OF STAYING CLEAR. INVERSION IS STILL STRONG AND THERE IS
A CHC THAT CIGS WILL LINGER INTO THE EARLY AFTERNOON. THERE WILL BE
AN EARLIER RETURN OF CIGS THIS EVENING.
.KLAX...ONLY FAIR CONFIDENCE IN TAF WITH A 30 PERCENT CHC OF IFR
CIGS LASTING UNTIL 20Z OR 21Z.
.KBUR...VERY GOOD CONFIDENCE IN CAVU TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...BRUNO
AVIATION...RORKE
SYNOPSIS...DB
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KLOX 051123
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
340 AM PDT SUN SEP 5 2010
.SYNOPSIS...
AN UPPER LOW MOVING INTO THE WEST COAST WILL BRING SOME COOLING TO
THE AREA TODAY. AS LOW PRESSURE STRENGTHENS OVER THE WEST...THE
COOLING TREND WILL CONTINUE THROUGH WEDNESDAY. THERE WILL BE AN
INCREASE IN NIGHT THROUGH MORNING LOW CLOUDS AND FOG IN COASTAL
AND VALLEY AREAS...WITH CLOUDS POSSIBLY REACHING THE COASTAL SLOPES
BY MID WEEK. SLIGHT WARMING IS EXPECTED FRIDAY AND SATURDAY.
&&
.SHORT TERM (TODAY-TUE)...WDSPRD LOW CLOUDS AND ON THE CENTRAL COAST
COAST THIS MORNING...AND CLOUDS HAVE BEGUN TO PUSH INTO THE SANTA
YNEZ VALLEY. CLOUDS WILL LIKELY PUSH INTO THE SALINAS VALLEY AS
WELL. ACROSS THE COASTAL WATERS...THERE HAS BEEN A RAPID EXPANSION
OF LOW CLOUDS ACROSS THE SANTA MONICA BASIN...AND CLOUDS SHOULD HAVE
NO TROUBLE PUSHING INTO CSTL SXNS OF L.A. AND VTU COUNTIES. OFFSHORE
N-S GRADS ACROSS SBA COUNTY MAY HOLD OFF STRATUS FOR A WHILE...BUT
EXPECT AT LEAST PATCHY COVERAGE NEAR THE COAST BY DAYBREAK. MARINE
LAYER HAS DEEPENED TO ABOUT 800 FEET OR SO...BUT SHOULD STILL BE
SHALLOW ENOUGH FOR SOME PATCHY DENSE FOG EARLY THIS MORNING. PROFILER
DATA SHOWS 4-6 DEGREES C OF COOLING BELOW 1000 FEET...WITH ABOUT 2-3
DEGREES C ABOVE THAT. ONSHORE GRADS BETWEEN LAX AND DAG WERE A
LITTLE MORE THAN 1 MB MORE ONSHORE THAN SAT AT THIS TIME. ALL OF
THERE FACTORS COMBINED SHOULD BRING NOTICEABLE COOLING TO MUCH OF
THE REGION TODAY...WITH TEMPS DOWN MOST SIGNIFICANTLY ACROSS INLAND
SECTIONS OF THE CSTL PLAIN AND IN THE LOWER VALLEYS. STILL...EXPECT
THE HOTTER MORE INTERIOR VALLEY LOCATIONS TO RISE WELL INTO THE
90S TODAY. THERE SHOULD BE A BIT LESS IN THE WAY OF COOLING IN THE
MTNS AND DESERTS TODAY. AND...NEAR THE COAST...NOT MUCH CHANGE IS
EXPECTED FROM THE CONTD VERY COOL CONDITIONS THAT HAS BEEN PERVASIVE
THIS SUMMER.
HEIGHTS WILL CONT TO LOWER ACROSS THE AREA TONIGHT AND MONDAY AS A
WEAK SHORT WAVE TROUGH DROPS THROUGH CA. N-S GRADS SHOULD BE SHARP
ENOUGH TO PRODUCE SOME GUSTY WINDS THROUGH AND BELOW PASSES AND
CANYONS OF THE SANTA YNEZ RANGE IN SRN SBA COUNTY AND POSSIBLY
THROUGH THE INTERSTATE 5 CORRIDOR TONIGHT. STRONG NWLY FLOW ACROSS
THE OUTER WATERS SHOULD CAUSE A DECENT EDDY TO SPIN UP...AND THIS
HAS BEEN ADVERTISED BY THE WRF FOR THE LAST COUPLE OF DAYS. EXPECT
WDSPRD LOW CLOUDS IN CSTL AREAS TONIGHT...AND THE EDDY SHOULD HELP
THE MARINE LAYER DEEPEN ENOUGH TO SEND CLOUDS INTO AT PORTIONS OF
THE L.A. AND VTU COUNTY VALLEYS TONIGHT. WITH THE NLY GRADS...CLOUDS
MAY HAVE A TOUGH TIME REACHING SRN SBA COUNTY...BUT BELIEVE THEY
WILL DO SO LATE AT NIGHT AFTER ANY GUSTY WINDS DIMINISH. TEMPS WILL
BE DOWN SIGNIFICANTLY IN MOST AREAS ON MONDAY...WITH ANOTHER 5 TO 10
DEGREES OFF MAX TEMPS IN MOST AREAS. THE EXCEPTION AGAIN WILL BE
NEAR THE CST WHERE WARMING OVER THE PAST FEW DAYS HAS BEEN MINIMAL.
THE WEAK TROUGH OVER THE AREA MON NIGHT AND TUE WILL BE KICKED
EASTWARD AS ANOTHER STRONGER TROUGH DIGS INTO THE PAC NW. THE MARINE
LAYER SHOULD DEEPEN...WITH NIGHT/MORNING LOW CLOUDS AND FOG IN ALL
CSTL AND MOST VALLEY AREAS. THERE WILL BE SEVERAL MORE DEGREES OF
COOLING IN MOST AREAS ON TUE...WITH TEMPS GENERALLY DOWN TO WELL
BELOW NORMAL LEVELS.
.LONG TERM (WED-SAT)...A STRONG UPPER LOW IS FCST TO DEVELOP OVER
THE PAC NW WED WITH A TROUGH EXTENDING SWD INTO SRN CA...THEN
THIS TROUGH AXIS SHOULD SWING THE E OF THE REGION ON THU. MARINE
LAYER SHOULD DEEPEN SUCH THAT LOW CLDS SHOULD REACH THE CSTL SLOPES
TUE NIGHT/WED MORNING...AND THERE WILL PROBABLY BE SOME DRIZZLE. WED
COULD BE A PARTIAL CLEARING TYPE OF DAY W OF THE MTNS...AND IT WILL
BE A VERY COOL DAY ACROSS THE REGION. THERE MAY BE ENOUGH COOLING
TO WIPE OUT THE MARINE LAYER WED NIGHT/THU...BUT FOR NOW...WILL KEEP
THE THEME OF WDSPRD NIGHT THRU MORNING CLOUDS/FOG. HEIGHTS WILL
BEGIN TO REBOUND A BIT FOR FRI AND SAT...BUT A BROAD TROUGH WILL
PERSIST...SO EXPECT TEMPS TO REMAIN BELOW NORMAL INTO SAT.
&&
.AVIATION...05/1135Z...WILL BE ISSUED SHORTLY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...BRUNO
AVIATION...RORKE
SYNOPSIS...
WWW.WEATHER.GOV/LOSANGELES
000
FXUS65 KPSR 051114
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
410 AM MST SUN SEP 5 2010
.SYNOPSIS...
EXPECT ANOTHER HOT DAY TODAY AS HIGH PRESSURE ALOFT PERSISTS OVER
THE SOUTHWEST UNITED STATES. THE WEATHER PATTERN WILL CHANGE DURING
THE NEXT FEW DAYS...WITH LOW PRESSURE ALOFT BECOMING THE DOMINANT
WEATHER FEATURE OVER THE WESTERN UNITED STATES. CONSEQUENTLY...
TEMPERATURES WILL TREND DOWNWARD DURING MUCH OF THE UPCOMING
WEEK...WITH BELOW NORMAL READINGS LIKELY WEDNESDAY THROUGH FRIDAY.
THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL OCCUR OVER
SOUTH-CENTRAL ARIZONA MONDAY NIGHT THROUGH TUESDAY EVENING.
&&
.DISCUSSION...
HIGH PRESSURE ALOFT WILL BRING ABOVE NORMAL DAYTIME HIGHS AGAIN
TODAY...THOUGH FORECAST SOUNDINGS SUGGEST MAX TEMPS WILL BE A COUPLE
DEGREES LOWER THAN WHAT OCCURRED SATURDAY. UPPER AIR PATTERN WILL
UNDERGO A SIGNIFICANT CHANGE DURING THE NEXT FEW DAYS...AS LOW
PRESSURE ALOFT BECOMES THE DOMINANT WEATHER FEATURE OVER THE WESTERN
UNITED STATES WHILE THE SUBTROPICAL HIGH IS SUPPRESSED FAR TO OUR
SOUTH AND EAST. A RATHER STRONG LOW PRESSURE SYSTEM AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...AND BRING DRY AND COOLER AIR TO THE REGION. 12Z 850 MB
TEMPS FORECAST TO LOWER FROM 26C TODAY TO 17-18C BY THURSDAY/
FRIDAY...WHEN BELOW NORMAL MAX AND MIN TEMPS ARE A GOOD BET. THIS
WEATHER CHANGE HAS BEEN WELL-ADVERTISED FOR SEVERAL DAYS NOW.
PRECIPITATION CHANCES DURING THIS TRANSITION HAVE BEEN TOUGHER TO
DEAL WITH...AS NUMERICAL MODELS THE PAST FEW DAYS HAVE PROVIDED
WIDELY DIVERGENT SOLUTIONS REGARDING DEGREE OF MOIST ADVECTION AND
STRENGTH/TRACK OF A WEAK WEATHER DISTURBANCE EMANATING FROM THE
SUBTROPICS IN ADVANCE OF THE AFOREMENTIONED LOW PRESSURE SYSTEM/COLD
FRONT. NAM/ECMWF/GFS HAVE NOW CONVERGED ON WHAT APPEARS TO BE A
REASONABLE SOLUTION...WITH MOIST ADVECTION OCCURRING PRIMARILY OVER
SOUTH-CENTRAL AZ MONDAY AFTN INTO TUESDAY AS WEAK DISTURBANCE
APPROACHES FROM THE SOUTHWEST. AT THE SAME TIME...UPPER LEVEL JET
STREAK ASSOCIATED WITH THE STRONG LOW PRESSURE SYSTEM STRENGTHENS TO
OUR NORTH...WITH EASTERN HALF OF OUR FORECAST AREA UNDER RIGHT-REAR
QUAD. MODEST DEGREE OF CAPE EXISTS IN FORECAST SOUNDINGS BY TUESDAY
MORNING...SO THUNDERSTORM POTENTIAL SHOULD EXIST. INTRODUCED SLIGHT
CHANCE FOR SHOWERS/THUNDERSTORMS MAINLY OVER SOUTH-CENTRAL AZ MONDAY
NIGHT THROUGH TUESDAY EVENING (PRECIP CHANCES MAY BE TOO
CONSERVATIVE...BUT AT LEAST PRECIP CHANCE HAS BEEN INTRODUCED OVER
PORTIONS OF THE LOWER DESERT). MUCH DRIER AIR OVERSPREADS THE ENTIRE
FORECAST AREA BY LATE WEDNESDAY...THEN PERSISTS THROUGH THE
REMAINDER OF THE WEEK. COULD SEE A BIT WARMER TEMPS BY NEXT WEEKEND
AS UPPER HIGH CENTERED OVER THE SOUTH-CENTRAL UNITED STATES
STRENGTHENS AND EXPANDS TOWARD THE WEST...HOWEVER...NUMERICAL MODELS
AGREE THAT MEAN LONG WAVE TROUGH POSITION WILL REMAIN OVER OR NEAR
THE WEST COAST FOR THE NEXT 7-10 DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
ISOLATED THUNDERSTORMS WILL GENERALLY REMAIN CONFINED BEYOND 60 NM
OF THE PHOENIX METRO AREA LATE THIS AFTERNOON. CHANCE FOR AN OUTFLOW
REACHING KPHX/KIWA IS EXTREMELY LOW. THUNDERSTORM IMPACTS LOOK LOW
AGAIN FOR SUNDAY.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
GENERALLY CLEAR SKIES AND LIGHT WINDS THROUGH SUNDAY AFTERNOON.
SOUTHERLY WINDS WILL INCREASE AT KBLH SUNDAY AFTERNOON AS A LOW
PRESSURE SYSTEM MOVES THROUGH THE INTERMOUNTAIN WEST. GUSTS TO 20KT
WILL BE POSSIBLE.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP
NEAR THE WEST COAST WITH COOLER WEATHER DURING THE MIDDLE OF THE
WEEK. THIS SYSTEM WILL ALSO RESULT IN BREEZY WINDS FROM THE SOUTHWEST
IN THE AFTERNOONS WITH GUSTS BETWEEN 20 AND 30 MPH TUESDAY AND
WEDNESDAY. THE AIR WILL BE DRY WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...DG
AVIATION...HIRSCH
FIRE WEATHER...ELLIS
000
FXUS66 KHNX 051113
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
413 AM PDT SUN SEP 5 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN AS A TROUGH OF LOW
PRESSURE BRUSHES THE REGION. THIS WILL BRING A SLIGHT COOLING
TREND THROUGH LABOR DAY. A STRONGER LOW PRESSURE SYSTEM WILL THEN
PROVIDE A MORE SIGNIFICANT COOLDOWN BY MIDWEEK AS IT PUSHES
THROUGH.
&&
.DISCUSSION...
HIGH TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR YESTERDAY
AFTERNOON WERE MOSTLY DOWN AROUND A DEGREE OR SO FROM HIGHS
FRIDAY. THE SLIGHT COOLING TREND WILL CONTINUE THROUGH LABOR DAY
AS THE RIDGE OVERHEAD FURTHER WEAKENS IN RESPONSE TO A TROUGH
BRUSHING THE REGION AS IT TRACKS OUT OF THE PACIFIC NORTHWEST.
THIS WILL ALSO BRING SOME GUSTY WINDS OVER THE SIERRA RIDGES AND
THROUGH AND BELOW THE PASSES OF THE KERN COUNTY MOUNTAINS BUT
EXPECTED TO REMAIN BELOW ADVISORY THRESHOLDS.
A MORE SIGNIFICANT COOLDOWN WILL THEN BE IN STORE THROUGH MIDWEEK
AS A FOLLOWING TROUGH DIGS FARTHER SOUTH ALONG THE COAST AND
SWINGS INLAND. TEMPERATURES ARE EXPECTED TO DECREASE FROM AROUND
CLIMO TUESDAY TO AS MUCH AS 10-15 DEGREES LOWER FOR WEDNESDAY/THURSDAY.
BREEZY CONDITIONS WILL AGAIN DEVELOP AS THE SYSTEM MOVES THROUGH
THE REGION TUESDAY NIGHT/WEDNESDAY. SLIGHT CHANCES FOR PRECIPITATION
OVER THE SIERRA NORTH OF KINGS CANYON REMAIN IN THE FORECAST FOR
WEDNESDAY INTO THURSDAY AS THE SYSTEM PASSES...THOUGH THE MODELS
SHOW LIMITED AVAILABLE MOISTURE.
TEMPERATURES ARE EXPECTED TO RECOVER SLIGHTLY BY FRIDAY...BUT
REMAINING GENERALLY BELOW SEASONAL AVERAGES INTO EARLY NEXT WEEK
AS ADDITIONAL SHORTWAVE ENERGY DROPS SOUTH TOWARD THE REGION.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 12Z MONDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...JEB
AVN/FW...DURFEE
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KEKA 051057
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
400 AM PDT SUN SEP 5 2010
.SYNOPSIS...A WEAK COOL FRONT WILL MOVE ACROSS NORTHWEST CALIFORNIA
TODAY...PRODUCING DRY NORTHERLY WINDS ALONG THE COAST AND A COOLING
TREND ACROSS THE INTERIOR.
&&
DISCUSSION...EARLY MORNING PICTURES FROM SPACE SHOWING SOME GROUND
FOG DEVELOPING DOWN THE 101 CORRIDOR SOUTH OF HUMBOLDT BAY AND
THROUGH THE EEL RIVER DRAINAGE. COASTSIDE THE ONLY CHANGE WILL BE
AN EXPECTED INCREASE IN NORTHERLY WINDS TODAY WHICH SHOULD KEEP MOST
COASTAL AREAS CLEAR AND WEED OUT THE GROUND FOG MENTIONED EARLY BY
MID MORNING. THE UPPER LEVEL MAPS SHOW A TROUGH MOVING ACROSS THE
PAC NW DRAGGING A WEAK COLD FRONT TOWARD NRN CA...RESULTING IN
COOLER TEMPS TODAY ACROSS THE INTERIOR... ~ 5 TO 10 DEGREES BEHIND
YESTERDAYS READINGS. BRIEF SHORTWAVE RIDGING MOVES OVERHEAD
BEGINNING TONIGHT AS A THERMAL TROUGH STRENGTHENS AND SHIFTS TOWARD
THE COAST. LIGHT OFFSHORE WINDS ARE EXPECTED AS WELL TONIGHT AND THE
EARLY PART OF MONDAY WHICH SHOULD MAINTAIN THE CLEAR SKIES ALONG THE
COAST BUT LITTLE IMPACT FOR FIRE WEATHER CONCERNS AS HIGHEST GUSTS
WILL BE VERY LOCALIZED ACROSS THE RIDGETOPS AND FAVORABLE TERRAIN.
A STRONGER TROUGH DROPPING SOUTH ALONG THE WEST COAST OF CANADA WILL
BEGIN TO AFFECT OUR WEATHER ON TUESDAY...FIRST WITH SIGNIFICANT
COOLING...MAINLY ACROSS THE INTERIOR. BOTH GFS AND EUROPEAN
FORECAST MODELS IN GOOD AGREEMENT BOTH SPATIALLY AND TEMPORALLY WITH
THIS FEATURE AND THE LIKELIHOOD OF GETTING SOME SPOTTY RAIN IS
INCREASING...AS WELL AS STRONGER ONSHORE FLOW BEGINNING TUE. THE
COLD POOL MOVES OVER NW CA TUE NIGHT PROVIDING OUR BEST SHOT FOR A
FEW LIGHT SHOWERS REGION WIDE. WEDNESDAY WILL BE THE CHILLIEST DAY
ACROSS THE INTERIOR WITH TEMPS STRUGGLING TO ACHIEVE THE MID 70S.
AFTER THE TROUGH MOVES THROUGH BY LATE WED...ECMWF AND GFS HAVE A
FLAT RIDGE BUILDING WITH A COUPLE OF MINOR SHORTWAVES MOVING INTO
THE PACIFIC NORTHWEST. STRONG WARMING IS UNLIKELY AND EXPECT DRY
WEATHER OVERALL.
AVIATION...SATELLITE FOG PRODUCT SHOWS THAT MARINE LAYER CLOUDS HAVE
MOVED DOWN THE EEL RIVER VALLEY AND SOME OF THE COASTAL HILLS NEAR
AND NORTH OF HUMBOLDT BAY. THESE CLOUDS WILL PRODUCE LOCAL IFR CIGS
BUT EXPECT THEM TO DISSIPATE BY MID MORNING AS BRISK NORTHERLY WINDS
DEVELOP OVER NEAR-COASTAL AREAS. EXPECT VFR TO PREVAIL OTHERWISE. CMC
MARINE...KEPT CURRENT WARNINGS IN PLACE AS MODELS CONTINUE TO DEPICT
SOLID GALE FORCE N WINDS OVER THE OUTER WATERS TODAY THROUGH MONDAY
EVENING. THE NEARSHORE BUOYS HAVE SHOWN GALE FORCE WIND GUSTS AT
TIMES THROUGH SATURDAY AFTERNOON AND EVENING...AND SHIP OBS HAVE
REPORTED WINDS OF 30 TO 35 KT SO FEEL THAT DATA IS BACKING UP THE
WARNINGS. THE BUOYS SHOW SEAS OF 11 TO 12 FT AT THE EEL RIVER AND
CAPE MENDO BUOYS...WITH 10 FT AT PT ARENA...INDICATING THAT THE
WARNING FOR SEAS IS ALSO JUSTIFIED. SWAN MODEL IS CALLING FOR SHORT
PERIOD SEAS BUILDING TO NEAR 16 FT OVER THE SOUTHERN OUTER
WATERS...AND FEEL THIS IS QUITE LIKELY BASED ON WHAT THE DATA SHOWS
THUS FAR. HAZ SEAS WARNING CURRENTLY COVERS ALL BUT THE NEAR SHORE
WATERS NORTH OF THE CAPE. THIS WILL NEED TO BE WATCHED...DEPENDING
ON HOW STRONGLY THE N WINDS FILL IN CLOSE TO SHORE.
OTHERWISE...FORECAST REMAINS ON TRACK FOR A DECREASING TREND IN BOTH
WINDS AND SEAS STARTING TUESDAY. CMC
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY PZZ450-455.
HAZARDOUS SEAS WARNING PZZ455.
GALE AND HAZARDOUS SEAS WARNING PZZ470-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS66 KSGX 051038
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
345 AM PDT SUN SEP 5 2010
.SYNOPSIS...
LOW PRESSURE ALONG THE WEST COAST WILL BRING COOLING THROUGH
THURSDAY WITH A DEEPER MARINE LAYER FOR MORE EXTENSIVE NIGHT AND
MORNING COASTAL LOW CLOUDS AND FOG. LOCALLY WINDY AT TIMES IN THE
MOUNTAINS AND DESERTS. A LITTLE WARMER FOR FRIDAY AND SATURDAY UNDER
WEAKER LOW PRESSURE.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
A TROUGH OF LOW PRESSURE MOVING INLAND THROUGH THE PACIFIC NORTHWEST
WILL INCREASE THE ONSHORE FLOW IN SOUTHWEST CALIFORNIA TODAY
BRINGING A FEW DEGREES OF COOLING FOR MOST AREAS...AND SEVERAL
DEGREES OF COOLING FOR SOME VALLEY AND INLAND COASTAL AREAS.
SATURDAY EVENING AIRCRAFT SOUNDINGS SHOWED A STRONG AND SHALLOW
MARINE INVERSION WITH THE BASE BELOW 1000 FEET. AREAS OF LOW CLOUDS
AND LOCALLY DENSE FOG WILL EXTEND LOCALLY INLAND THIS MORNING...
POSSIBLY AS FAR AS THE WESTERNMOST VALLEYS IN SAN DIEGO COUNTY...
THEN CLEAR BACK TO NEAR THE BEACHES FOR THE AFTERNOON. THE STRONGER
ONSHORE FLOW WILL BRING GUSTY ONSHORE WINDS TO THE MOUNTAINS AND
DESERTS FOR LATE AFTERNOON THROUGH LATE EVENING.
FOR MONDAY...CONTINUED SLOW COOLING AND SLOW DEEPENING OF THE MARINE
LAYER UNDER WEAK LOW PRESSURE.
FOR TUESDAY THROUGH THURSDAY...ANOTHER TROUGH OF LOW PRESSURE WILL
AMPLIFY ALONG THE WEST COAST BRINGING COOLING TO WELL BELOW SEASONAL
AVERAGES...A DEEPER MARINE LAYER...AND GUSTY ONSHORE WINDS IN THE
MOUNTAINS AND DESERTS.
FOR FRIDAY AND SATURDAY...SLOW WARMING UNDER WEAKER LOW PRESSURE.
&&
.AVIATION...
050845Z...MARINE LAYER IS VERY SHALLOW THIS MORNING WITH THE CLOUD
BASES 200-300 FEET MSL AND CLOUD TOPS TO AROUND 600 FEET. FOG HAS
IMPACTED KCRQ AND KSAN THIS MORNING WITH VARIABLE VISIBILITIES FROM
FROM 1/4 TO 1 MILE. EXPECT THE SKIES TO CLEAR AND THE FOG TO LIFT AT
BETWEEN 15-17Z WITH VIS IMPROVING TO 6SM. STRATUS/FOG WILL REMAIN
NEAR THE BEACHES INTO THE AFTERNOON.
ONSET OF THE STRATUS AND DENSE FOG AT KSNA WILL ARRIVE A LITTLE
LATER...BTWN 11-12Z..AND BURN OFF BY 16Z.
TONIGHT THE STRATUS WILL ARRIVE EARLIER...POSSIBLY AS EARLY AS 03Z
AT KSAN AND KCRQ...AND 05Z AND KSNA. CIGS AND VIS WILL BE HIGHER AS
THE MARINE LAYER DEEPENS AHEAD OF AN ADVANCING LOW PRESSURE TROUGH.
ABOVE THE MARINE LAYER...MOSTLY CLEAR SKIES AND UNRESTRICTED
VISIBILITIES THROUGH MONDAY MORNING.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...MARTIN
AVIATION/MARINE...MOEDE
NWS ON THE WEB AT WEATHER.GOV/SANDIEGO
000
FXUS66 KSTO 051008
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
300 AM PDT SUN SEP 5 2010
.DISCUSSION...
UPPER RIDGE CONTINUES TO FLATTEN AS A STRONG UPPER SHORT-WAVE TROUGH
MOVES THROUGH THE PACNW. THIS SYSTEM WILL MOVE INTO THE NORTHERN
ROCKIES THIS AFTERNOON WITH A TRAILING DRY COLD FRONT MOVING INTO
NORTHERN CALIFORNIA. TEMPERATURES WILL CONTINUE THEIR GRADUAL
DESCENT TODAY WITH THE GREATEST AIRMASS COOLING EXPECTED TO OCCUR
ACROSS THE NORTHERN ZONES AS THE COLD FRONT MOVES IN. COOLING WILL
NOT BE AS GREAT ACROSS THE SOUTHERN ZONES AS MINOR AIRMASS COOLING
IS EXPECTED TO BE OFFSET BY A TRANSITION TO NORTHERLY SURFACE FLOW.
LOCALLY BREEZY NORTH TO NORTHEAST WINDS WILL DEVELOP BEHIND THE
FRONT THIS AFTERNOON INTO TONIGHT AS SUBSIDENCE AND COLD ADVECTION
INCREASE. LESS BREEZY CONDITIONS WILL RETURN BY EARLY LABOR DAY AS
BRIEF SHORT-WAVE RIDGING RETURNS LEADING TO A LITTLE WARMING FOR
MUCH OF THE FORECAST AREA.
A MUCH DEEPER TROUGH CONTINUES TO BE ADVERTISED BY THE MODELS FOR
MIDWEEK...SIMILAR TO THE SYSTEM THAT AFFECTED THE REGION LAST
WEEKEND. THIS SYSTEM IS EXPECTED TO BRING A CHANCE OF SHOWERS ALONG
WITH MUCH COOLER TEMPERATURES WEDNESDAY INTO THURSDAY. 00Z THURSDAY
(WEDNESDAY AFTERNOON PDT) 500 MB ANOMOLIES PROGGED TO BE AROUND 3
STANDARD DEVIATIONS BELOW NORMAL. SHORT-WAVE RIDGING FORECAST TO
BRING DRIER AND WARMER WEATHER LATE IN THE WEEK BEFORE THE TROUGH
DEEPENS AGAIN LATE NEXT WEEKEND.
&&
.AVIATION...
VFR CONDITIONS WITH CLEAR SKIES EXPECTED FOR TODAY AND TONIGHT. MAIN
AVIATION ISSUE FOR TODAY WILL BE NORTHERLY WINDS INCREASING THROUGH
THE DAY. GUSTS THIS AFTERNOON OF 25 KT ARE POSSIBLE ACROSS THE
NORTHERN AND CENTRAL SACRAMENTO VALLEY...TO AROUND 20 KT AROUND THE
SACRAMENTO AND NORTHERN SAN JOAQUIN VALLEYS. THESE VALLEY WINDS WILL
GRADUALLY DECREASE SUNDAY NIGHT WITH NORTHEASTERLY WINDS IN THE
MOUNTAINS INCREASING THROUGH FAVORED CANYONS AND PASSES.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS66 KMTR 050906
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
206 AM PDT SUN SEP 5 2010
.DISCUSSION...AS OF 2:06 AM PDT SUNDAY...A ROBUST NORTH-TO-SOUTH
FLOW HAS SCOURED LOW CLOUDS FROM THE COAST FROM NORTHERN SANTA CRUZ
COUNTY NORTHWARD. SATELLITE IMAGERY SHOWS STRATUS IN A STRAIGHT LINE
FROM SANTA CRUZ COUNTY SOUTHWARD TO WEST OF POINT CONCEPTION..AS
WELL AS INTO THE ENTIRE SALINAS VALLEY...WITH CLEAR SKIES ELSEWHERE.
LAST HOUR SURFACE PRESSURE GRADIENTS WERE 5.9 MB FROM ARCATA TO
SFO...7.1 MB FROM SFO TO LAS...AND 3.0 MB FROM SFO TO SAC.
STRONG NORTHERLY FLOW AS HIGH PRESSURE BRIEFLY BUILDS OFFSHORE WILL
PROVIDE A BIT OF A WARMING TREND FOR TODAY ACROSS THE DISTRICT WITH
TEMPERATURES WARMING TO THE 60S AND 70S AT THE COAST...TO THE 80S AND
90S INLAND...WITH SOME OF THE WARMEST INTERIOR AREAS EXCEEDING 100
DEGREES. LATE TONIGHT AN OFFSHORE FLOW IS FORECAST TO DEVELOP WITH
BREEZES PICKING UP ACROSS THE NORTH BAY HILLS. THE LATEST NAM KEEPS
WIND SPEEDS AT OR BELOW 35 KNOTS AT 925 MB...ERGO WIND ADVISORIES ARE
NOT ANTICIPATED BEING NECESSARY. WARMER CONDITIONS ARE THEN EXPECTED
ACROSS THE DISTRICT ON MONDAY. HOWEVER BY TUESDAY...A SHARP COOLING
TREND IS EXPECTED AS A DEEP TROUGH OF LOW PRESSURE DROPS SOUTHWARD
INTO NORTHERN CALIFORNIA FROM THE GULF OF ALASKA. THIS TROUGH IS THEN
PROGGED TO REMAIN ALONG THE WEST COAST FOR THE REMAINDER OF THE
FORECAST PERIOD KEEPING TEMPERATURES ON THE COOL SIDE WITH EPISODES
OF NIGHT AND MORNING LOW CLOUDS...FOG AND DRIZZLE ALONG THE COAST.
&&
.AVIATION...AS OF 4:20 PM PDT SATURDAY...NORTHERLY GRADIENT IS
INCREASING AND NOW ALMOST 6 MB FROM ACV-SFO. STRATUS IS CLEARING
ALONG THE NORTH COAST AND WITH ONLY A MODERATE ONSHORE GRADIENT
EXPECT JUST SCATTERED STRATUS AND VFR CONDITIONS FOR THE SAN
FRANCISCO BAY REGION OVERNIGHT.
.VICINITY OF KSFO...VFR CONDITIONS EXPECTED OVERNIGHT WITH
JUST SCATTERED STRATUS LATER TONIGHT. GUSTY WEST TO NORTHWEST WINDS
TO 25 KT CONTINUING THROUGH 04Z THEN DECREASING TO LESS THAN 10 KT
BY 08Z.
.KSFO BRIDGE APPROACH...SAME AS VICINITY OF KSFO.
.MRY BAY AREA TERMINALS...IFR CIGS WILL LIKELY REDEVELOP BETWEEN 01-
03Z THIS EVENING. CLEARING EXPECTED EARLIER ON SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDA...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: SSA
AVIATION/MARINE: WJK
000
FXUS65 KREV 050823
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
123 AM PDT SUN SEP 5 2010
.SHORT TERM...
HARDLY ANY CHANGES MADE TO PREVIOUS FORECAST WITH THE MAIN
CONCERNS STILL THE EASTERLY WINDS ON LAKE TAHOE SUNDAY NIGHT AND
MONDAY MORNING AS WELL AS THE LOW TEMPS MONDAY AND TUESDAY
MORNINGS THROUGH COLDER VALLEY LOCATIONS.
DRY COLD FRONT WILL PUSH THROUGH THE CWA TODAY WITH TEMPERATURES
FIRST DROPPING ACROSS THE NORTHERN ZONES FOLLOWED BY THE SOUTHERN
ZONES LATE THIS AFTERNOON. NEARLY 15 DEGREES OF COOLING CAN BE
EXPECTED IN THE NORTH WITH ABOUT 5 DEGREES IN THE SOUTH. WINDS
WILL BECOME NORTHERLY BEHIND THE FRONT WITH GUSTS CONTINUING INTO
THE NIGHT.
AS THE ASSOCIATED UPPER TROUGH SLIDES TO THE EAST...IT WILL SET UP
AN EASTERLY PRESSURE GRADIENT SUNDAY NIGHT INTO MONDAY MORNING
WHICH DOES BRING UP CONCERNS FOR LAKE TAHOE. LATEST GUIDANCE IS
NOT QUITE AS STRONG WITH THE WINDS AS IT WAS FOR THE DAYTIME
FORECAST PACKAGE...BUT WITH THIS BEING A HOLIDAY WEEKEND...FEEL IT
IS PRUDENT TO KEEP THE LAKE WIND ADVISORY IN PLACE. WIND WAVES OF
2-3 FEET CAN BE EXPECTED ON THE WEST SHORE OF LAKE TAHOE. THOSE
WITH ACTIVITIES PLANNED ON THE LAKE NEED TO TAKE CAUTION...
ESPECIALLY IF IN A SMALLER WATERCRAFT.
A DRY AIR MASS MOVES INTO THE REGION MONDAY MORNING WHICH WILL
HELP TO MAXIMIZE RADIATIONAL COOLING. TEMPERATURES MONDAY MORNING
WILL BE SEASONABLY COLD WITH LOW IN THE UPPER 20S TO LOWER 30S FOR
MANY SIERRA VALLEYS AND OUTLYING WESTERN NEVADA VALLEYS. THOSE
WITH SENSITIVE OUTDOOR PLANTS OR OUTDOOR PETS SHOULD TAKE THE
PROPER PRECAUTIONS. PLEASE SEE THE SPECIAL WEATHER STATEMENT
/RNOSPSREV/ FOR ADDITIONAL DETAILS. THE OTHER CONCERN WITH THE DRY
AIR MASS MOVING INTO THE REGION IS THE PLUNGING RELATIVE HUMIDITY
VALUES DURING THE DAY...WITH MODERATE TO POOR RECOVERIES MONDAY
AND TUESDAY.
A COLD UPPER LOW WILL DROP DOWN THE PACIFIC NORTHWEST COAST
TUESDAY INTO WEDNESDAY...WITH THE EC SLIGHTLY SLOWER THAN THE GFS
BRINGING IT INLAND. HAVE KEPT THE SLIGHT CHANCE POPS EARLY
WEDNESDAY MORNING IN THE NW ZONES...HOWEVER DID TRIM THEM BACK A
BIT AS I THINK THE SLOWER TIMING OF THE EC IS MORE ACCURATE AS THE
HIGHLY AMPLIFIED SYSTEM WILL LIKELY DIG FURTHER SOUTH BEFORE
MOVING INLAND. WINDS WILL INCREASE AHEAD OF THE SYSTEM WITH GUSTY
SOUTHWEST TO WEST WINDS TUESDAY AFTERNOON AND EVENING. DF
.LONG TERM...WEDNESDAY THROUGH SATURDAY...
UPPER TROUGH STILL PROGGED TO DROP INTO THE WEST COAST EARLY IN
PERIOD WITH ANOMALIES 2-3 SDEV BELOW NORMAL IN THE TEMP/HEIGHT
FIELDS ASSOCIATED WITH CORE OF UPPER LOW. THE 00Z ECMWF HAS COME
BACK IN LINE WITH A DEEPER AND SLOWER PROGRESSION AND SO HAVE
MAINTAINED PREVIOUS FORECAST THINKING OF UNSETTLED WED-THU WITH
TEMPERATURES BELOW MOS GUIDANCE. MAINTAINED A SLIGHT CHANCE OF
THUNDER FOR EASTERN ZONES WED AFTERNOON AND EVENING ASSOCIATED WITH
CONVERGENCE ALONG COLD FRONT AND LARGE SCALE LIFT FROM INCOMING
100+KT UPPER JET ROUNDING BASE OF TROUGH. ANOTHER WINDY DAY IS
EXPECTED WED ESPECIALLY FOR THE SIERRA FRONT SOUTHWARD INTO
MONO-MINERAL COUNTIES. GENERAL CLOUDINESS AND SHOWERS UNDER TROUGH
THU WILL BE MOST NUMEROUS ACROSS THE NORTHERN HALF OF THE AREA. DID
INTRODUCE A SLIGHT CHANCE OF LINGERING SHOWERS THU EVENING TO
ACCOUNT FOR SLIGHTLY SLOWER SOLUTION THAN IS SHOWN IN THE
OPERATIONAL GFS.
TEMPERATURES TO MODERATE FRI-SAT AS UPPER LOW LIFTS NORTHEASTWARD
AND FLOW BECOMES MORE ZONAL TO SOUTHWEST ALOFT. THERE ARE SOME
SIGNALS THAT THERE MAY BE ENOUGH MOISTURE AND INSTABILITY ACROSS FAR
NORTHERN AREAS FOR A FEW SHOWERS BY LATE SAT. THIS IS AHEAD OF
ANOTHER DEVELOPING WEST COAST TROUGH THAT MAY AFFECT THE REGION THE
FOLLOWING WEEK. FOR NOW WILL SHOW SOME LOW POPS IN THE GRIDDED
FORECAST BUT LEAVE MENTION OUT OF THE TEXT FORECASTS. HOHMANN
&&
.AVIATION...
VFR AT TAF SITES. TROUGH BRUSHING AREA TO THE NORTH WILL PUSH A COLD
FRONT SOUTHWARD THROUGH THE AREA THIS MORNING AND BRING WINDS TO A
MORE NORTHWEST TO NORTH DIRECTION BY THIS AFTERNOON AND THEN
NORTHEAST TO EAST TONIGHT. HOHMANN
&&
.FIRE WEATHER...
A COLD FRONT WILL PUSH THROUGH WESTERN NV TODAY AND BRING WINDS MORE
TO THE NORTH BY THIS AFTERNOON. SOME GUSTS COULD APPROACH 30 MPH
OVER THE BASIN AND RANGE NEAR AND IMMEDIATELY BEHIND THIS FRONT.
THESE GUSTY WINDS AND LOW AFTERNOON HUMIDITY MAY CREATE CRITICAL
FIRE WEATHER CONDITIONS ON A LOCALIZED AND SHORT TERM BASIS AND THE
HEADLINE WILL BE MAINTAINED. WINDS CLOSER TO THE LEE OF THE SIERRA
WILL BE A BIT LESS ALTHOUGH VERY DRY CONDITIONS WILL CONTINUE
TODAY.
NEXT DAY OF CONCERN WILL BE TUESDAY AS SOUTHWEST FLOW INCREASES
AHEAD OF A STRONGER TROF DROPPING INTO THE NWRN US. SOME UNCERTAINTY
STILL EXISTS IN TIMING AS PEAK WINDS MAY BE DELAYED UNTIL TUES
NIGHT. IF THIS SYSTEM STILL SHOWS THIS TRACK AND STRENGTH WITH
UPCOMING MODEL RUNS...THEN A WATCH MAY BE NEEDED. MJD/HOHMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 10 PM SUNDAY TO 10 AM PDT MONDAY FOR
LAKE TAHOE IN NVZ002.
CA...LAKE WIND ADVISORY FROM 10 PM SUNDAY TO 10 AM PDT MONDAY FOR
LAKE TAHOE IN CAZ072.
&&
$$
HTTP://WEATHER.GOV/RENO
000
FXUS66 KLOX 050538 AAA
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1035 PM PDT SAT SEP 4 2010
UPDATED AVIATION SECTION
.SYNOPSIS...
SUNDAY WILL BEGIN A COOLING TREND TO THE AREA...ESPECIALLY
INLAND...AS A LOW PRESSURE SYSTEM GRADUALLY MOVES DOWN THE COAST
INTO CALIFORNIA BY MIDWEEK. BELOW NORMAL TEMPERATURES WILL CONTINUE
MONDAY THROUGH THE END OF THE WEEK...WITH AN INCREASE IN THE MARINE
LAYER.
&&
.SHORT TERM (TONIGHT-TUE)...MARINE LAYER STILL QUITE SHALLOW THIS
EVENING...AROUND 700 FT DEEP AT LAX. LOW CLOUDS WERE MOVING INLAND
ALONG THE CENTRAL COAST THIS EVENING AND WILL CONTINUE TO AFFECT THE
AREA OVERNIGHT ALONG WITH PATCHY DENSE FOG. S OF POINT CONCEPTION...
LOW CLOUDS WERE GENERALLY WEST OF THE ISLANDS BUT WERE EDGING
EASTWARD AND SHOULD MOVE TO THE COASTAL AREAS OVERNIGHT. PATCHY
DENSE FOG WILL ALSO BE LIKELY WITH THE LOW CLOUDS. PATCHY LOW CLOUDS
AND DENSE FOG SHOULD ALSO AFFECT THE SALINAS VALLEY LATE TONIGHT.
OTHERWISE MOST OF THE FORECAST AREA WILL REMAIN MOSTLY CLEAR THRU
THE NIGHT.
AN UPPER LEVEL HIGH OVER SRN CA THIS EVENING WILL WEAKEN THRU SUN AS
AN UPPER LEVEL TROF MOVES INTO NORTHERN CA. WEAK UPPER TROFFINESS IS
EXPECTED FOR MON OVER THE REGION...FOLLOWED BY A BROAD UPPER LEVEL
TROF MOVING INTO THE REGION FROM THE NORTH ON TUE. DRY WEATHER WILL
PREVAIL OVER THE AREA THRU TUE. IT LOOKS LIKE THE MARINE LAYER
PATTERN WILL PERSIST THRU TUE WITH NIGHT AND MORNING LOW CLOUDS AND
FOG PREVAILING OVER THE COASTAL PLAIN AND MOVING INTO THE VALLEYS AS
THE MARINE LAYER DEEPENS. AN EDDY IS EXPECTED TO PERSIST OVER THE
SOCAL BIGHT NIGHT AND MORNING HOURS WHICH WILL ALSO HELP THE MARINE
LAYER TO DEEPEN. OTHERWISE MOSTLY CLEAR SKIES CAN BE EXPECTED THRU
TUE. GUSTY AFTERNOON WINDS CAN BE EXPECTED IN THE ANTELOPE VALLEY
SUN AND TUE...AND GUSTY NORTHERLY CANYON WINDS WILL BE POSSIBLE
ALONG THE SBA S COAST AND MTNS SUN EVENING. TEMPS AWAY FROM THE
IMMEDIATE COAST ARE EXPECTED TO BE ABOUT 6 TO 12 DEG COOLER ON SUN
AND FALL TO NEAR NORMAL TO SLIGHTLY ABOVE NORMAL. FURTHER COOLING
WILL TAKE PLACE MON AND TUE...WITH HIGHS BY TUE SEVERAL DEGREES
BELOW NORMAL FOR MOST AREAS.
***FROM PREVIOUS DISCUSSION***
.LONG TERM (WED-SAT)...TEMPS SHOULD BOTTOM OUT WED AS THE TROF AXIS
FINALLY SWINGS INLAND DURING THE AFTERNOON. A MUCH WEAKER IMPULSE
MOVING INTO THE PAC NW THU AND FRI WILL MAINTAIN THE TROF AND
CYCLONIC FLOW ALONG THE WEST COAST, SO SOME REBOUND OF TEMPS IS
EXPECTED BUT MINIMAL.
&&
.AVIATION...05/0535Z...LIFR CONDS WDSPRD ON THE CENTRAL COAST...AND
ARE EXPECTED TO PUSH INTO CSTL SXNS OF L.A. AND VTU COUNTIES
OVERNIGHT. S CST OF SBA COUNTY IS NOT AS CERTAIN. CIGS SHOULD BURN
OFF IN MOST AREAS BY LATE MORNING.
KLAX...GENERALLY LOW TO MODERATE CONFIDENCE IN TAF. THERE IS A 20-30
PERCENT CHANCE THAT CIGS WILL REMAIN ABOVE 1NM IN BR. THERE IS A 20
PERCENT CHANCE THAT CIGS WILL ARRIVE AS EARLY AS 09Z.
KBUR...HIGH CONFIDENCE IN CAVU TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...SIRARD/WOFFORD
AVIATION...DB
SYNOPSIS...BARTLING
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KLOX 050413
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
910 PM PDT SAT SEP 4 2010
.SYNOPSIS...
SUNDAY WILL BEGIN A COOLING TREND TO THE AREA...ESPECIALLY
INLAND...AS A LOW PRESSURE SYSTEM GRADUALLY MOVES DOWN THE COAST
INTO CALIFORNIA BY MIDWEEK. BELOW NORMAL TEMPERATURES WILL CONTINUE
MONDAY THROUGH THE END OF THE WEEK...WITH AN INCREASE IN THE MARINE
LAYER.
&&
.SHORT TERM (TONIGHT-TUE)...MARINE LAYER STILL QUITE SHALLOW THIS
EVENING...AROUND 700 FT DEEP AT LAX. LOW CLOUDS WERE MOVING INLAND
ALONG THE CENTRAL COAST THIS EVENING AND WILL CONTINUE TO AFFECT THE
AREA OVERNIGHT ALONG WITH PATCHY DENSE FOG. S OF POINT CONCEPTION...
LOW CLOUDS WERE GENERALLY WEST OF THE ISLANDS BUT WERE EDGING
EASTWARD AND SHOULD MOVE TO THE COASTAL AREAS OVERNIGHT. PATCHY
DENSE FOG WILL ALSO BE LIKELY WITH THE LOW CLOUDS. PATCHY LOW CLOUDS
AND DENSE FOG SHOULD ALSO AFFECT THE SALINAS VALLEY LATE TONIGHT.
OTHERWISE MOST OF THE FORECAST AREA WILL REMAIN MOSTLY CLEAR THRU
THE NIGHT.
AN UPPER LEVEL HIGH OVER SRN CA THIS EVENING WILL WEAKEN THRU SUN AS
AN UPPER LEVEL TROF MOVES INTO NORTHERN CA. WEAK UPPER TROFFINESS IS
EXPECTED FOR MON OVER THE REGION...FOLLOWED BY A BROAD UPPER LEVEL
TROF MOVING INTO THE REGION FROM THE NORTH ON TUE. DRY WEATHER WILL
PREVAIL OVER THE AREA THRU TUE. IT LOOKS LIKE THE MARINE LAYER
PATTERN WILL PERSIST THRU TUE WITH NIGHT AND MORNING LOW CLOUDS AND
FOG PREVAILING OVER THE COASTAL PLAIN AND MOVING INTO THE VALLEYS AS
THE MARINE LAYER DEEPENS. AN EDDY IS EXPECTED TO PERSIST OVER THE
SOCAL BIGHT NIGHT AND MORNING HOURS WHICH WILL ALSO HELP THE MARINE
LAYER TO DEEPEN. OTHERWISE MOSTLY CLEAR SKIES CAN BE EXPECTED THRU
TUE. GUSTY AFTERNOON WINDS CAN BE EXPECTED IN THE ANTELOPE VALLEY
SUN AND TUE...AND GUSTY NORTHERLY CANYON WINDS WILL BE POSSIBLE
ALONG THE SBA S COAST AND MTNS SUN EVENING. TEMPS AWAY FROM THE
IMMEDIATE COAST ARE EXPECTED TO BE ABOUT 6 TO 12 DEG COOLER ON SUN
AND FALL TO NEAR NORMAL TO SLIGHTLY ABOVE NORMAL. FURTHER COOLING
WILL TAKE PLACE MON AND TUE...WITH HIGHS BY TUE SEVERAL DEGREES
BELOW NORMAL FOR MOST AREAS.
***FROM PREVIOUS DISCUSSION***
.LONG TERM (WED-SAT)...TEMPS SHOULD BOTTOM OUT WED AS THE TROF AXIS
FINALLY SWINGS INLAND DURING THE AFTERNOON. A MUCH WEAKER IMPULSE
MOVING INTO THE PAC NW THU AND FRI WILL MAINTAIN THE TROF AND
CYCLONIC FLOW ALONG THE WEST COAST, SO SOME REBOUND OF TEMPS IS
EXPECTED BUT MINIMAL.
&&
.AVIATION...05/0000Z...GENERALLY HI CONFIDENCE IN THE CURRENT TAF
PACKAGE. IFR/LIFR CONDITIONS ARE LIKELY AT ALL COASTAL TAF SITES
STARTING FROM EARLY THIS EVENING TO LATER TONIGHT...AND LINGERING
THROUGH MUCH OF SUN MORNING BEFORE IMPROVING TO VFR BY LATE MORNING.
A BRIEF PERIOD OF LIFR CONDITIONS WILL ALSO AFFECT KPRB 13Z-16Z SUN
MORNING. ELSEWHERE VFR CONDITIONS ARE EXPECTED THRU SUN.
KLAX...GENERALLY HI CONFIDENCE IN THE CURRENT TAF...ALTHO TIMING OF
ONSET OF LOW CLOUDS TONIGHT MAY BE AN HOUR OR TWO TOO EARLY.
IFR/LIFR CONDITIONS ARE EXPECTED TO MOVE INTO THE AIRFIELD AROUND
07Z THEN PERSIST THRU ABOUT 16Z SUN...WITH VFR CONDITIONS EXPECTED
IN THE AFTERNOON. IFR CIGS SHOULD RETURN AROUND 04Z SUN EVENING.
KBUR...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU SUN.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...SIRARD/WOFFORD
AVIATION...SIRARD
SYNOPSIS...BARTLING
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KSTO 050413
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
915 PM PDT SAT SEP 4 2010
.DISCUSSION...
TEMPERATURES ACROSS INTERIOR NORTHERN CALIFORNIA ARE RUNNING
ANYWHERE BETWEEN 2 TO 6 DEGREES COOLER TONIGHT THAN THEY WERE THIS
TIME LAST NIGHT...INDICATING A FLATTENING OF THE RIDGE. AS EXPECTED
WITH THE EASTERLY POSITIONING OF TROF AXIS...UPVALLEY GRADS ARE
DECREASING INDICATING WINDS WILL BEGIN SWITCHING TOWARD A MORE
WEST-NORTHWEST TO NORTHWEST DIRECTION. HAVE UPDATED GRIDS TO REFLECT
WINDS ACCORDINGLY. DAY TIME VISIBLE SAT IMAGERY SHOWED DRASTIC
REDUCTION IN MARINE STRATUS AS OFFSHORE WINDS BEGIN TO INCREASE.
MODELS INDICATE A SMALL PIECE OF ENERGY SLIDING SOUTH ACROSS
NORTHERN CALIFORNIA TOMORROW...BUT DUE TO LOW RH EXPECT MINIMAL IF
ANY CLOUD DEVELOPMENT.
OVERNIGHT TEMPERATURES HAVE BEEN INCREASED A FEW DEGREES IN THE
FOOTHILL REGIONS TO REFLECT SLIGHT CHANGES IN 500MB HEIGHTS. HIGH
TEMPERATURES TOMORROW FORECAST TO BE SLIGHTLY COOLER THAN TODAY AS
TROF AXIS PASSES OVERHEAD TO THE NORTHEAST. TIGHTENING GRADIENTS
SHOW THAT TOMORROW MAY END UP BEING BREEZY IN THE NORTHERN
SACRAMENTO VALLEY... WITH WRF MODEL SURFACE WINDS APPROACHING 25 KTS
IN THE REDDING/RED BLUFF AREA. ASN/PALMER
&&
.AVIATION...DRY UPPER LEVEL SYSTEM MOVING ACROSS THE PACIFIC
NORTHWEST THIS EVENING WILL DIG INTO THE GREAT BASIN OVER THE NEXT
24 HOURS. AS A RESULT...VFR CONDITIONS WILL CONTINUE TO
PREVAIL...WITH CLEAR SKIES. HOWEVER...UPPER LEVEL WINDS WILL
TRANSITION FROM WESTERLY THIS EVENING TO NORTH AND NORTHEAST LATE
TONIGHT AND ON SUNDAY. LOCALLY GUSTY NORTH SURFACE WINDS UP TO 25
KTS WILL BE POSSIBLE DOWN THE VALLEY AND AT KRDD AND KRBL
TOMORROW...BEFORE TRANSITIONING TO NORTHEAST AND EASTERLY FAVORED
CANYONS AND PASSES TOMORROW NIGHT. PALMER
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS65 KPSR 050407
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
910 PM MST SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN TO WEAKEN SUNDAY AS A LOW PRESSURE SYSTEM
PASSES TO THE NORTH...THOUGH TEMPERATURES WILL REMAIN WELL ABOVE
NORMAL. A COOLING TREND CAN BE EXPECTED MONDAY THROUGH THURSDAY AS A
DEEPER TROUGH OF LOW PRESSURE MOVES THROUGH THE WESTERN STATES. IN
FACT...SLIGHTLY BELOW NORMAL TEMPERATURES WILL PREVAIL ACROSS THE
REGION WEDNESDAY THROUGH SATURDAY. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX
THROUGH TUESDAY BEFORE DRY AIR OVERSPREADS THE REGION.
&&
.DISCUSSION...
WITH NON-EXISTENT CAPE ACROSS THE LOWER ELEVATIONS...CONVECTION WAS
MAINLY CONFINED TO THE PEAKS OF THE MOGOLLON RIM THIS AFTERNOON.
CLOUDS ARE CURRENTLY DISSIPATING ACROSS NORTHERN MARICOPA COUNTY.
OTHERWISE...SKIES ARE CLEAR ACROSS THE FORECAST AREA. OUT WEST...THE
EXCESSIVE HEAT WARNING WAS ALLOWED TO EXPIRE AT 8 PM. TEMPERATURES
WILL REMAIN WELL ABOVE AVERAGE BUT BELOW EXCESSIVE HEAT CRITERIA
SUNDAY.
PREVIOUS DISCUSSION...
BOTH THE NAM AND GFS SHOW LESS MOISTURE AROUND SUNDAY AS THEY DEPICT
SOMETHING OF A SOUTHWARD EBB. DESPITE THE ANTICYCLONE OVER US BEING
PUSHED EASTWARD DUE TO A TROUGH MOVING THROUGH THE NORTHWEST
STATES...ANTICIPATE LITTLE CHANGE IN TEMPERATURES. THE COOLING WILL
LAG AND BE MORE NOTICEABLE ON MONDAY. A CYCLONIC CIRCULATION AT THE
LOWER AND MID LEVELS NEAR BAJA IS ADVERTISED TO PULL SOME MOISTURE
NORTHWARD INTO OUR FORECAST AREA MONDAY AND TUESDAY AS IT SLOWLY
MOVES EASTWARD. FOR MONDAY THIS OCCURS MAINLY OVER THE LOWER DESERTS
OF OUR ARIZONA ZONES THEN SHIFTS EASTWARD TUESDAY TO THE HIGHER
TERRAIN...INCLUDING ZONE 24. FORECAST SOUNDINGS NOT SUPPORTING
ENOUGH INSTABILITY TO INTRODUCE POPS ON THE LOWER DESERTS. MADE A
SLIGHT ADJUSTMENT TO EXPAND THE AREA OF SLIGHT CHANCES OVER ZONE 24
FOR TUESDAY. MEANWHILE ANOTHER TROUGH IN THE WESTERLIES MOVES INTO
THE WESTERN STATES TUESDAY FOR SOME BREEZY CONDITIONS AND MODEST
ADDITIONAL COOLING...MORE NOTICEABLE OVER OUR WESTERN AREAS...WITH
TEMPS NEAR NORMAL.
IN THE EXTENDED...ECMWF AND GFS AGREE THAT BROAD TROUGHING WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A STRONG LOW
PRESSURE SYSTEM MOVING THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...PASSING MOSTLY TO THE NORTH BUT BRINGING IN DRY AIR TO
THE REGION. FORECAST TEMPS SHOULD LOWER TO SLIGHTLY BELOW NORMAL
WEDNESDAY THROUGH SATURDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
ISOLATED THUNDERSTORMS WILL GENERALLY REMAIN CONFINED BEYOND 60 NM
OF THE PHOENIX METRO AREA LATE THIS AFTERNOON. CHANCE FOR AN OUTFLOW
REACHING KPHX/KIWA IS EXTREMELY LOW. THUNDERSTORM IMPACTS LOOK LOW
AGAIN FOR SUNDAY.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
GENERALLY CLEAR SKIES AND LIGHT WINDS THROUGH SUNDAY AFTERNOON.
SOUTHERLY WINDS WILL INCREASE AT KBLH SUNDAY AFTERNOON AS A LOW
PRESSURE SYSTEM MOVES THROUGH THE INTERMOUNTAIN WEST. GUSTS TO 20KT
WILL BE POSSIBLE.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP
NEAR THE WEST COAST WITH COOLER WEATHER DURING THE MIDDLE OF THE
WEEK. THIS SYSTEM WILL ALSO RESULT IN BREEZY WINDS FROM THE SOUTHWEST
IN THE AFTERNOONS WITH GUSTS BETWEEN 20 AND 30 MPH TUESDAY AND
WEDNESDAY. THE AIR WILL BE DRY WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH/AJ
AVIATION...HIRSCH
FIRE WEATHER...ELLIS
000
FXUS66 KEKA 050400
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
855 PM PDT SAT SEP 4 2010
.SYNOPSIS...A WEAK COOL FRONT WILL MOVE ACROSS NORTHWEST CALIFORNIA
THIS WEEKEND...PRODUCING ROBUST NORTHERLY WINDS ALONG THE COAST AND
A COOLING TREND ACROSS THE INTERIOR.
&&
.UPDATE...UPDATED FORECAST TO DECREASE SKY COVER TONIGHT IN
COASTAL AREAS AND DECREASE TEMPS. SATELLITE FOG PRODUCT HAS ONLY
CLOUDS EXTENDING FROM JUST EAST OF HUMBOLDT BAY SE OVER COASTAL
MOUNTAINS INTO BRIDEVILLE. MFR AND OAK SOUNDINGS HAD ABOUT 2-5
DEGRESS COOLING ALOFT AND WITH STRONG WINDS OVER MARINE AREA
EXPECT TO HAVE WELL MIXED MARINE LAYER AND FEWER CLOUDS. LATEST
NAM MODEL SEEMS TO HAVE GOOD ANALYSIS OF THIS AND IT ONLY DEVELOPS
STRATUS AROUND HUMBOLDT BAY LATE TONIGHT AND CLEARING IT QUICKLY
SUNDAY MORNING. UPDATED SKY GRIDS ACCORDINGLY AND DECREASED TEMPS
TONIGHT WITH LESS CLOUD COVER AND LOWER DEWPOINTS. DEAN
&&
.PREV DISCUSSION... /ISSUED 318 PM PDT SAT SEP 4 2010/
DISCUSSION...THE UPPER LEVEL PATTERN CONSISTS OF A TROUGH MOVING
ACROSS THE PAC NW DRAGGING A WEAK COLD FRONT TOWARD NRN CA. TEMPS
TODAY ARE RUNNING 5 TO 10 DEGREES BEHIND YESTERDAYS READINGS.
PLENTY OF STRATUS ALONG THE COAST AND OVER THE WATER THIS MORNING
IS BREAKING UP THIS AFTERNOON AS NORTH WINDS CONTINUE TO
INCREASE. CLOUDS WILL RETURN TO THE COAST OVERNIGHT...ESPECIALLY
NORTH OF THE CAPE AS THE WINDS WILL HELP PILE THE CLOUDS IN AROUND
THE BAY. SHORTWAVE RIDGING MOVES OVERHEAD BEGINNING SUNDAY EVENING
AS A THERMAL TROUGH STRENGTHENS AND SHIFTS TOWARD THE COAST.
OFFSHORE WINDS ARE EXPECTED SUNDAY NIGHT AND THE FIRST HALF OF
MONDAY WITH GUSTS AS HIGH AS 30 MPH EXPECTED ACROSS THE RIDGETOPS.
HUMIDITY RECOVERIES WILL BE POOR AS A RESULT AND THIS WILL BE
ADDRESSED WITHIN THE APPROPRIATE FIRE WX PRODUCTS. ANOTHER
MANIFESTATION OF THE OFFSHORE WINDS WILL BE TO BREAK UP THE MARINE
LAYER AND PUSH IT WELL OFFSHORE. AS A RESULT...WE EXPECT LABOR DAY
TO BE A MOSTLY SUNNY DAY ALONG WITH WARMER TEMPS.
A STRONGER TROUGH DROPPING SOUTH ALONG THE WEST COAST OF CANADA WILL
BEGIN TO AFFECT OUR WEATHER ON TUESDAY...FIRST WITH SIGNIFICANT
COOLING...MAINLY ACROSS THE INTERIOR. MODELS HAVE BEEN TRACKING
THIS LOW JUST OFF THE WEST COAST...ALLOWING IT TO PICK UP A
LITTLE MORE MOISTURE AS IT HEADS FOR NRN CA...BEFORE THEN SHIFTING
EAST. WITH STRONG ONSHORE FLOW BEGINNING TUE...A FEW SHOWERS ARE A
REAL POSSIBILITY...ESPECIALLY FOCUSED ALONG THE HIGHER TERRAIN.
THE COLD POOL MOVES OVER NW CA TUE NIGHT PROVIDING OUR BEST SHOT
FOR A FEW LIGHT SHOWERS REGION WIDE. WEDNESDAY WILL BE THE
CHILLIEST DAY ACROSS THE INTERIOR WITH TEMPS STRUGGLING TO ACHIEVE
THE MID 70S. AFTER THE TROUGH MOVES THROUGH BY LATE WED...ECMWF
AND GFS HAVE A FLAT RIDGE BUILDING WITH A COUPLE OF MINOR
SHORTWAVES MOVING INTO THE PACIFIC NORTHWEST. STRONG WARMING IS
UNLIKELY AND EXPECT DRY WEATHER OVERALL. JCA
AVIATION...UPDATED 855PM...CLOUDS WILL BE LIMITED TO AROUND
HUMBOLDT BAY AND SURROUNDING COASTAL HILLS TONIGHT AS STRATUS SEEN
ON FOG PRODUCT... AND REPORTED ON PIREP 10-15 MILES INLAND WILL
BUILD BACK TOWARD COAST. EXPECT IFR CEILINGS AT FIRST AND THEN
LIFR CIGS AND VSBY AROUND DAYBREAK. CLOUDS WILL QUICKLY DISSIPATE
BY MID MORNING WITH GUSTY NW WINDS DEVELOPING ALL COASTAL AREAS.
EXPECT VFR TO PREVAIL ELSEWHERE INLAND. DEAN
MARINE...NO CHANGES MADE TO ANY OF THE CURRENT WARNINGS. NORTH
WINDS WILL CONTINUE TO INCREASE TONIGHT INTO SUNDAY AS THE SURFACE
PRESSURE GRADIENT TIGHTENS. AS A RESULT, SUSTAINED WINDS OF 25 TO 35
KT WITH GUSTS UP TO 45 KT ARE EXPECTED OVER THE OUTER WATERS THROUGH
MONDAY. THE STRONGEST WINDS ARE EXPECTED SUNDAY AFTERNOON. ALONG
WITH THE WINDS, STEEP SHORT PERIOD SEAS WILL BUILD ACROSS THE OUTER
WATERS TO NEAR 15 FT AT 8 SECONDS. THE HAZARDOUS SEAS WILL PROPAGATE
INTO THE SOUTHERN INNER WATERS TOMORROW, SO KEPT THAT WARNING GOING.
THE NORTHERN INNER WATERS WILL REMAIN UNDER A SCA DUE TO WINDS AND
SEAS. THE PRESSURE GRADIENT WILL BEGIN TO EASE ON TUESDAY, ALLOWING
WINDS TO FALL AND SEAS TO SUBSIDE. STROZ
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY PZZ450-455.
HAZARDOUS SEAS WARNING PZZ455.
GALE AND HAZARDOUS SEAS WARNING PZZ470-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS66 KEKA 050355
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
855 PM PDT SAT SEP 4 2010
. SYNOPSIS...A WEAK COOL FRONT WILL MOVE ACROSS NORTHWEST
CALIFORNIA THIS WEEKEND...PRODUCING ROBUST NORTHERLY WINDS ALONG
THE COAST AND A COOLING TREND ACROSS THE INTERIOR.
&&
.UPDATE...UPDATED FORECAST TO DECREASE SKY COVER TONIGHT IN
COASTAL AREAS AND DECREASE TEMPS. SATELLITE FOG PRODUCT HAS ONLY
CLOUDS EXTENDING FROM JUST EAST OF HUMBOLDT BAY SE OVER COASTAL
MOUNTAINS INTO BRIDEVILLE. MFR AND OAK SOUNDINGS HAD ABOUT 2-5
DEGRESS COOLING ALOFT AND WITH STRONG WINDS OVER MARINE AREA
EXPECT TO HAVE WELL MIXED MARINE LAYER AND FEWER CLOUDS. LATEST
NAM MODEL SEEMS TO HAVE GOOD ANALYSIS OF THIS AND IT ONLY DEVELOPS
STRATUS AROUND HUMBOLDT BAY LATE TONIGHT AND CLEARING IT QUICKLY
SUNDAY MORNING. UPDATED SKY GRIDS ACCORDINGLY AND DECREASED TEMPS
TONIGHT WITH LESS CLOUD COVER AND LOWER DEWPOINTS. DEAN
&&
.PREV DISCUSSION... /ISSUED 318 PM PDT SAT SEP 4 2010/
DISCUSSION...THE UPPER LEVEL PATTERN CONSISTS OF A TROUGH MOVING
ACROSS THE PAC NW DRAGGING A WEAK COLD FRONT TOWARD NRN CA. TEMPS
TODAY ARE RUNNING 5 TO 10 DEGREES BEHIND YESTERDAYS READINGS.
PLENTY OF STRATUS ALONG THE COAST AND OVER THE WATER THIS MORNING
IS BREAKING UP THIS AFTERNOON AS NORTH WINDS CONTINUE TO
INCREASE. CLOUDS WILL RETURN TO THE COAST OVERNIGHT...ESPECIALLY
NORTH OF THE CAPE AS THE WINDS WILL HELP PILE THE CLOUDS IN AROUND
THE BAY. SHORTWAVE RIDGING MOVES OVERHEAD BEGINNING SUNDAY EVENING
AS A THERMAL TROUGH STRENGTHENS AND SHIFTS TOWARD THE COAST.
OFFSHORE WINDS ARE EXPECTED SUNDAY NIGHT AND THE FIRST HALF OF
MONDAY WITH GUSTS AS HIGH AS 30 MPH EXPECTED ACROSS THE RIDGETOPS.
HUMIDITY RECOVERIES WILL BE POOR AS A RESULT AND THIS WILL BE
ADDRESSED WITHIN THE APPROPRIATE FIRE WX PRODUCTS. ANOTHER
MANIFESTATION OF THE OFFSHORE WINDS WILL BE TO BREAK UP THE MARINE
LAYER AND PUSH IT WELL OFFSHORE. AS A RESULT...WE EXPECT LABOR DAY
TO BE A MOSTLY SUNNY DAY ALONG WITH WARMER TEMPS.
A STRONGER TROUGH DROPPING SOUTH ALONG THE WEST COAST OF CANADA WILL
BEGIN TO AFFECT OUR WEATHER ON TUESDAY...FIRST WITH SIGNIFICANT
COOLING...MAINLY ACROSS THE INTERIOR. MODELS HAVE BEEN TRACKING
THIS LOW JUST OFF THE WEST COAST...ALLOWING IT TO PICK UP A
LITTLE MORE MOISTURE AS IT HEADS FOR NRN CA...BEFORE THEN SHIFTING
EAST. WITH STRONG ONSHORE FLOW BEGINNING TUE...A FEW SHOWERS ARE A
REAL POSSIBILITY...ESPECIALLY FOCUSED ALONG THE HIGHER TERRAIN.
THE COLD POOL MOVES OVER NW CA TUE NIGHT PROVIDING OUR BEST SHOT
FOR A FEW LIGHT SHOWERS REGION WIDE. WEDNESDAY WILL BE THE
CHILLIEST DAY ACROSS THE INTERIOR WITH TEMPS STRUGGLING TO ACHIEVE
THE MID 70S. AFTER THE TROUGH MOVES THROUGH BY LATE WED...ECMWF
AND GFS HAVE A FLAT RIDGE BUILDING WITH A COUPLE OF MINOR
SHORTWAVES MOVING INTO THE PACIFIC NORTHWEST. STRONG WARMING IS
UNLIKELY AND EXPECT DRY WEATHER OVERALL. JCA
AVIATION...UPDATED 855PM...CLOUDS WILL BE LIMITED TO AROUND
HUMBOLDT BAY AND SURROUNDING COASTAL HILLS TONIGHT AS STRATUS SEEN
ON FOG PRODUCT... AND REPORTED ON PIREP 10-15 MILES INLAND WILL
BUILD BACK TOWARD COAST. EXPECT IFR CEILINGS AT FIRST AND THEN
LIFR CIGS AND VSBY AROUND DAYBREAK. CLOUDS WILL QUICKLY DISSIPATE
BY MID MORNING WITH GUSTY NW WINDS DEVELOPING ALL COASTAL AREAS.
EXPECT VFR TO PREVAIL ELSEWHERE INLAND. DEAN
MARINE...NO CHANGES MADE TO ANY OF THE CURRENT WARNINGS. NORTH
WINDS WILL CONTINUE TO INCREASE TONIGHT INTO SUNDAY AS THE SURFACE
PRESSURE GRADIENT TIGHTENS. AS A RESULT, SUSTAINED WINDS OF 25 TO 35
KT WITH GUSTS UP TO 45 KT ARE EXPECTED OVER THE OUTER WATERS THROUGH
MONDAY. THE STRONGEST WINDS ARE EXPECTED SUNDAY AFTERNOON. ALONG
WITH THE WINDS, STEEP SHORT PERIOD SEAS WILL BUILD ACROSS THE OUTER
WATERS TO NEAR 15 FT AT 8 SECONDS. THE HAZARDOUS SEAS WILL PROPAGATE
INTO THE SOUTHERN INNER WATERS TOMORROW, SO KEPT THAT WARNING GOING.
THE NORTHERN INNER WATERS WILL REMAIN UNDER A SCA DUE TO WINDS AND
SEAS. THE PRESSURE GRADIENT WILL BEGIN TO EASE ON TUESDAY, ALLOWING
WINDS TO FALL AND SEAS TO SUBSIDE. STROZ
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY PZZ450-455.
HAZARDOUS SEAS WARNING PZZ455.
GALE AND HAZARDOUS SEAS WARNING PZZ470-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS66 KHNX 050349
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
849 PM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL WEAKEN SUNDAY AS A TROUGH OF LOW
PRESSURE MOVES INTO THE REGION. THIS WILL BRING COOLER TEMPERATURES
TEMPERATURES FOR LABOR DAY AND THE FIRST PART OF NEXT WEEK.
&&
.DISCUSSION...THE UPPER RIDGE OVER CENTRAL AND SOUTHERN CALIFORNIA
WILL CONTINUE TO WEAKEN TONIGHT AND SUNDAY AS THE UPPER TROUGH
OVER THE PACIFIC NORTHWEST MOVES INTO THE NORTHERN ROCKIES AND THE
GREAT BASIN SUNDAY AFTERNOON. WITH THE COLDER AIR DROPPING INTO
THE GREAT BASIN...THERE WILL BE A SLOW COOLING TREND ACROSS THE
CENTRAL CALIFORNIA INTERIOR SUNDAY THROUGH TUESDAY. NOT MUCH
MOISTURE WILL THIS SYSTEM...BUT COULD SEE LOCALLY GUSTY WINDS
ACROSS THE KERN MOUNTAINS AND DESERT AND OVER THE CREST OF THE
SIERRA.
ANOTHER TROUGH OF LOW PRESSURE WILL DROP OUT OF THE GULF OF ALASKA
AND INTO PACIFIC NORTHWEST TUESDAY AND INTO CALIFORNIA TUESDAY
NIGHT AND WEDNESDAY. THIS SYSTEM WILL BRING MORE SIGNIFICANT
COOLING TO CENTRAL CALIFORNIA ON WEDNESDAY ALONG WITH INCREASING
ONSHORE SURFACE PRESSURE GRADIENTS. GUSTY WINDS WILL LIKELY OCCUR
THROUGH THE COASTAL MOUNTAINS PASSES INTO THE SAN JOAQUIN VALLEY
TUESDAY AFTERNOON AND TUESDAY NIGHT. AS THE UPPER TROUGH AXIS
PUSHES THROUGH CENTRAL CALIFORNIA WEDNESDAY BREEZY CONDITIONS
SHOULD DEVELOP IN THE SAN JOAQUIN VALLEY AS A 90KT JET ALIGNS WITH
THE ONSHORE GRADIENTS. EXPECT THE STRONGER WINDS TO OCCUR THROUGH
BELOW MOUNTAIN PASSES OF KERN COUNTY. SOME LIGHT PRECIPITATION MAY
BE POSSIBLE OVER THE SIERRA WEDNESDAY INTO THURSDAY MORNING
ALTHOUGH THE GFS CONTINUES TO TREND DRIER THAN THE ECMWF.
TEMPERATURES WILL BE ABOUT 10 DEGREES BELOW NORMAL WEDNESDAY AND
THURSDAY. TEMPERATURES WILL WARM SLIGHTLY FRIDAY BUT A WESTERLY
FLOW ALOFT WILL MAINTAIN BELOW SEASONAL TEMPERATURE FOR THE
REMAINDER OF THE WEEK.
&&
.AVIATION...
AS THE BASE OF THE U/L TROUGH BRUSHES BY SUN AFTN AND EVNG SOME
GUSTY WINDS WILL BE POSSIBLE ACROSS THE SIERRA RIDGETOPS AND THROUGH
AND BELOW KERN COUNTY PASSES...GUSTS UP TO 40 KTS WILL BE POSSIBLE
THERE. OTHERWISE...VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL
CALIFORNIA INTERIOR THROUGH 06Z MONDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...BEAN
AVN/FW...DCH
SYNOPSIS...BEAN
WEATHER.GOV/HANFORD
000
FXUS66 KSGX 050342
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 PM PDT SAT SEP 4 2010
.SYNOPSIS...COOLER NEXT WEEK AS A SERIES OF UPPER LEVEL LOW PRESSURE
SYSTEMS MOVE PAST TO THE NORTH. A SHALLOW MARINE LAYER TONIGHT WILL
BECOME DEEPER THROUGH MID WEEK FOR MORE EXTENSIVE LOW CLOUDS AND FOG
WEST OF THE MOUNTAINS DURING THE NIGHTS AND MORNINGS. LOCALLY WINDY
AT TIMES IN THE MOUNTAINS AND DESERTS.
&&
.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
.SHORT TERM (TONIGHT-TUESDAY)...SKIES WERE CLEAR THIS EVENING EXCEPT
FOR PATCHES OF STRATUS NEAR THE COAST. THE 00Z NKX SOUNDING HAD AN
INVERSION BASED NEAR 1000 FT WITH SE TO E WINDS THROUGH THE MID
LEVELS. ONSHORE GRADIENTS WITH ABOUT 5 MB SAN-IPL.
THE UPPER HIGH WILL WEAKEN SUNDAY IN RESPONSE TO A TROUGH MOVING
PAST TO THE N. ANOTHER UPPER LOW WILL DIG INTO THE PAC NW WITH A
TROUGH EXTENDING OVER SRN CA THROUGH TUESDAY. THIS WILL BRING A
COOLING TREND. MAX TEMPS WILL BE NEAR OR A LITTLE ABOVE SEASONAL
AVERAGES INLAND SUNDAY BUT A LITTLE BELOW AVERAGE NEAR THE COAST.
MAX TEMPS WILL BE WELL BELOW SEASONAL AVERAGES W OF THE MOUNTAINS BY
TUESDAY.
A SHALLOW MARINE LAYER TONIGHT WILL KEEP LOW CLOUDS AND FOG CONFINED
TO THE COASTAL AREAS AND FAR WRN SAN DIEGO INLAND VALLEYS. FOG WILL
BE LOCALLY DENSE. THE MARINE LAYER WILL DEEPEN SUNDAY AND MONDAY
NIGHTS WITH AN INTERMITTENT COASTAL EDDY. STRATUS WILL EXTEND INTO
MOST OF THE SAN DIEGO INLAND VALLEYS AND THE WRN INLAND EMPIRE BY
MONDAY NIGHT.
STRONGER ONSHORE FLOW AND WINDS ALOFT WILL CAUSE LOCAL GUSTY WINDS
IN THE MOUNTAINS AND DESERTS...MAINLY DURING THE AFTERNOONS AND
EVENINGS SUNDAY AND TUESDAY. THE CONTINUED DRY CONDITIONS AT THE
HIGHER ELEVATIONS AND DESERTS COMBINED WITH INCREASING WINDS WILL
INCREASE THE FIRE WEATHER HAZARD. HOWEVER...THE COOLER WEATHER WILL
MITIGATE THIS SOMEWHAT AND WIDESPREAD SUSTAINED CRITICAL FIRE
WEATHER CONDITIONS ARE NOT EXPECTED.
&&
.LONG TERM (WEDNESDAY-SATURDAY)...THE UPPER TROUGH WILL CONTINUE TO
DEEPEN OVER THE WEST THROUGH WEDNESDAY WHICH WILL BE THE COOLEST DAY
OF THE WEEK. MAX TEMPS WILL BE ABOUT 8 TO 16 DEGREES BELOW SEASONAL
AVERAGES AND THERE COULD BE SOME NEAR RECORD LOW MAX TEMPS
WEDNESDAY. SLIGHTLY WARMER THURSDAY AS THE TROUGH MOVES E THEN A
LITTLE MORE WARMING FRIDAY AND SATURDAY AS HEIGHTS RECOVER UNDER
WEAKER TROUGHING. EVEN WITH THE WARMING...MOST MAX TEMPS WILL REMAIN
BELOW SEASONAL AVERAGES.
A DEEP MARINE LAYER WEDNESDAY AND THURSDAY WILL ALLOW STRATUS TO GET
INTO THE LOWER COASTAL MOUNTAIN SLOPES DURING THE NIGHTS AND
MORNINGS. ONLY PARTIAL AFTERNOON CLEARING IN THE COASTAL AREAS. THE
MARINE LAYER WILL BECOME SHALLOWER WITH BETTER CLEARING FRIDAY AND
SATURDAY.
&&
.AVIATION...
050340Z...MARINE LAYER REMAINS VERY SHALLOW...LESS THAN 600 FEET
DEEP. COASTAL FOG BECAME JUST PATCHY THIS EVENING IN
CENTRAL/SOUTHERN SAN DIEGO COUNTY WITH CLEAR SKIES FURTHER NORTH.
FOG/LOW STRATUS WILL EXPAND AGAIN AFTER 06Z ON THE SAN DIEGO COUNTY
COAST AND COULD MOVE INTO COASTAL AIRPORTS...INCLUDING KSAN AND KCRQ
AROUND 09Z OR 10Z. TIMING OF STRATUS/FOG ON THE ORANGE COUNTY
COAST...INCLUDING NEAR KSNA IS UNCERTAIN BUT PROBABLY WILL BE IN THE
10Z TO 12Z RANGE. WHERE STRATUS/FOG OCCURS...VIS WILL MOSTLY BE ONE
MILE OR LESS...LOCALLY LESS THAN 1/4 MILE. CLEARING OF THE COASTAL
AIRPORTS SHOULD OCCUR BY 16Z...BUT AGAIN SOME STRATUS/FOG WILL
REMAIN NEAR THE BEACHES. STRATUS SHOULD ARRIVE EARLIER SUNDAY
NIGHT...POSSIBLY AS EARLY AS 03Z AT COASTAL AIRPORTS...BUT CIGS WILL
BE HIGHER AND VIS WILL BE BETTER THAN THOSE EXPECTED LATE TONIGHT.
ABOVE THE MARINE LAYER...MOSTLY CLEAR SKIES AND UNRESTRICTED
VISIBILITIES WILL CONTINUE THROUGH SUNDAY NIGHT.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...ATKIN
AVIATION...MAXWELL
000
FXUS66 KMTR 050332
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
832 PM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 8:32 PM PDT SATURDAY...LIGHT ON SHORE FLOW
IS RESULTING IN SLIGHTLY COOLER TEMPERATURES THIS EVENING.
TEMPERATURES ARE RUNNING ABOUT 5 TO 10 DEGREES COOLER THAN THIS HOUR
YESTERDAY. THE FORT ORD PROFILER IS INDICATING A SHALLOW MARINE
LAYER AROUND TWELVE HUNDRED FEET DEEP AND THE LATEST SATELLITE IR
FOG PRODUCT IS SHOWING SOME STRATUS ALONG THE COAST FROM THE
GOLDEN GATE SOUTH INTO SOUTHERN MONTEREY COUNTY. STRATUS IS PUSHING
INTO THE SALINAS VALLEY AT THIS HOUR. THE CURRENT FORECAST PACKAGE
SEEMS TO DEPICT THIS SCENARIO WELL AND DOES NOT REQUIRE ANY
UPDATES.
A TROUGH OF LOW PRESSURE IS EXPECTED TO DIVE INTO THE GREAT BASIN
OVERNIGHT INTO TOMORROW AS A THERMAL TROUGH BEGINS TO BUILD OVER
CALIFORNIA. THIS WILL RESULT IN OFFSHORE FLOW DEVELOPING FIRST OVER
THE NORTHBAY HILLS AND SPREADING SOUTH. THE OFFSHORE FLOW WILL
PROVIDE WARMER TEMPERATURES ACROSS A MAJORITY OF THE FORECAST AREA
AND WILL ALSO RESULT IN DRIER CONDITIONS ALONG THE RIDGELINES.
THESE WARMER CONDITIONS AND CLEAR SKIES ARE EXPECTED TO LAST INTO
LABOR DAY. LABOR DAY TEMPS ALONG THE COAST SHOULD BE IN THE 70S...
WITH 80S TO LOWER 90S AROUND THE BAY...AND THE 90S INLAND. INTERIOR
SECTIONS OF MONTEREY AND SAN BENITO COUNTIES COULD TOP THE CENTURY
MARK.
PREVIOUS DISCUSSION...THE WARM SPELL WILL BE SHORT-LIVED AS A TROUGH
DEEPENS AND DROPS SOUTH ALONG THE WEST COAST. TUESDAY WILL BE
SIGNIFICANTLY COOLER THAN MONDAY WITH FURTHER COOLING ON WEDNESDAY.
THE MARINE LAYER SHOULD DEEPEN TO OVER 2000 FEET BY LATE TUESDAY
NIGHT/WEDNESDAY MORNING SUPPORTING DRIZZLE ALONG THE COAST. MEDIUM
RANGE MODELS KEEP THE TROUGH ALONG THE COAST RESULTING IN COOLER THAN
NORMAL TEMPS ALONG WITH STRATUS ALONG THE COAST...SURGING INTO THE
VALLEYS DURING THE NIGHT AND MORNING HOURS.
&&
.AVIATION...AS OF 4:20 PM PDT SATURDAY...NORTHERLY GRADIENT IS
INCREASING AND NOW ALMOST 6 MB FROM ACV-SFO. STRATUS IS CLEARING
ALONG THE NORTH COAST AND WITH ONLY A MODERATE ONSHORE GRADIENT
EXPECT JUST SCATTERED STRATUS AND VFR CONDITIONS FOR THE SAN
FRANCISCO BAY REGION OVERNIGHT.
.VICINITY OF KSFO...VFR CONDITIONS EXPECTED OVERNIGHT WITH
JUST SCATTERED STRATUS LATER TONIGHT. GUSTY WEST TO NORTHWEST WINDS
TO 25 KT CONTINUING THROUGH 04Z THEN DECREASING TO LESS THAN 10 KT
BY 08Z.
.KSFO BRIDGE APPROACH...SAME AS VICINITY OF KSFO.
.MRY BAY AREA TERMINALS...IFR CIGS WILL LIKELY REDEVELOP BETWEEN 01-
03Z THIS EVENING. CLEARING EXPECTED EARLIER ON SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: LARRY/MHS
AVIATION/MARINE: WJK
000
FXUS66 KLOX 050002 AAA
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
500 PM PDT SAT SEP 4 2010
UPDATE FOR NEW AVIATION DISCUSSION
.SYNOPSIS...
SUNDAY WILL BEGIN A COOLING TREND TO THE AREA...ESPECIALLY
INLAND...AS A LOW PRESSURE SYSTEM GRADUALLY MOVES DOWN THE COAST
INTO CALIFORNIA BY MIDWEEK. BELOW NORMAL TEMPERATURES WILL CONTINUE
MONDAY THROUGH THE END OF THE WEEK...WITH AN INCREASE IN THE MARINE
LAYER.
&&
.SHORT TERM (TODAY-TUE)...TODAY WILL BE THE LAST OF THE BIG HEAT FOR
A WHILE AS HIGH PRESSURE OVER THE SOUTHWESTERN U.S. WEAKENS IN
RESPONSE TO A TROF MOVING INTO THE PAC NW. MOST INLAND AREAS SUNDAY
SHOULD SEE SEVERAL DEGREES OF COOLING AS ONSHORE FLOW STRENGTHENS.
INCREASING NORTHWEST FLOW AROUND PT CONCEPTION WILL BRING SOME WIND
THROUGH THE CANYONS OF THE SANTA YNEZ RANGE AND MAY BE ENOUGH TO
KEEP THE CLOUDS OUT OF SRN SBA COUNTY ALL TOGETHER. OTHERWISE, THE
MARINE LYR COVERAGE SUNDAY MORNING SHOULD BE PRETTY SIMILAR TO THIS
MORNING.
THE INCREASING NW WIND OFFSHORE SHOULD EVENTUALLY FORCE THE
DEVELOPMENT OF AN EDDY CIRCULATION OVER THE BIGHT REGION EITHER
SUNDAY NIGHT OR MONDAY MORNING. THIS WOULD TYPICALLY RESULT IN A
DEEPENING OF THE MARINE LYR AND MORE SIGNIFICANT COOLING MONDAY
AFTERNOON. AT THE SAME TIME THOUGH, WITH THE TROF MOVING INLAND SOME
NORTH TO NORTHEAST WINDS ALOFT ARE EXPECTED TO DEVELOP. THIS MAY
OFFSET AT LEAST SOME OF THE IMPACTS OF THE EDDY CIRCULATION AND
MARINE LYR COVERAGE MAY NOT BE AS WIDESPREAD AS PREVIOUSLY THOUGHT.
THE NAM RUNS THIS MORNING SHOWED 15-20 KT OF NORTHEAST WIND AT 850
MB THROUGH THE SANTA CLARA RIVER VALLEY SO WILL HAVE TO MONITOR THIS
TO SEE IF FUTURE RUNS CONTINUE THIS IDEA. FOR NOW, THOUGH, THE
FORECAST WAS LEFT PRETTY MUCH ALONE FOR MONDAY, INDICATING 5-10
DEGREES OF ADDITIONAL COOLING MOST AREAS WITH LOW CLOUDS REACHING
WELL INTO THE VALLEYS.
THE EDDY IS EXPECTED TO EXPAND TUESDAY WHILE AT THE SAME TIME THE
TROF ALONG THE WEST COAST DEEPENS. AS A RESULT, FURTHER COOLING OF
AFTERNOON TEMPERATURES IS EXPECTED WITH GREATER MARINE LYR COVERAGE.
.LONG TERM (WED-SAT)...TEMPS SHOULD BOTTOM OUT WED AS THE TROF AXIS
FINALLY SWINGS INLAND DURING THE AFTERNOON. A MUCH WEAKER IMPULSE
MOVING INTO THE PAC NW THU AND FRI WILL MAINTAIN THE TROF AND
CYCLONIC FLOW ALONG THE WEST COAST, SO SOME REBOUND OF TEMPS IS
EXPECTED BUT MINIMAL.
&&
.AVIATION...05/0000Z...GENERALLY HI CONFIDENCE IN THE CURRENT TAF
PACKAGE. IFR/LIFR CONDITIONS ARE LIKELY AT ALL COASTAL TAF SITES
STARTING FROM EARLY THIS EVENING TO LATER TONIGHT...AND LINGERING
THROUGH MUCH OF SUN MORNING BEFORE IMPROVING TO VFR BY LATE MORNING.
A BRIEF PERIOD OF LIFR CONDITIONS WILL ALSO AFFECT KPRB 13Z-16Z SUN
MORNING. ELSEWHERE VFR CONDITIONS ARE EXPECTED THRU SUN.
KLAX...GENERALLY HI CONFIDENCE IN THE CURRENT TAF...ALTHO TIMING OF
ONSET OF LOW CLOUDS TONIGHT MAY BE AN HOUR OR TWO TOO EARLY.
IFR/LIFR CONDITIONS ARE EXPECTED TO MOVE INTO THE AIRFIELD AROUND
07Z THEN PERSIST THRU ABOUT 16Z SUN...WITH VFR CONDITIONS EXPECTED
IN THE AFTERNOON. IFR CIGS SHOULD RETURN AROUND 04Z SUN EVENING.
KBUR...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU SUN.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...WOFFORD
AVIATION...SIRARD
SYNOPSIS...BARTLING
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KMTR 042340
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
440 PM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 2:30 PM PDT SATURDAY...TODAY ENDED UP BEING
SIGNIFICANTLY COOLER THAN WAS EXPECTED. EARLIER THIS AFTERNOON
UPDATED THE TEMP GRIDS FOR TODAY...BUT IT STILL WAS COOLER THAN
EXPECTED. HOWEVER...SATL IMAGERY IS SHOWING A CHANGE IN THE WEATHER
FOR THE DISTRICT AS STRATUS HAS BEEN DECREASING OVER NORTHWEST CA AS
A SFC NORTHERLY FLOW STRENGTHENS. THIS CAN BE SEEN IN THE GRADIENT
PICTURE WHICH SHOWS THE ARCATA-SFO GRADIENT IS NORTHERLY AT 4.9 MB...
AN INCREASE OF MORE THAN 2 MB SINCE THE MORNING. THE SFO-SAC GRADIENT
IS ONSHORE AT 2.4 MB.
AS A SHORTWAVE CONTINUES TO MOVE INTO THE ROCKIES A SFC HIGH WILL
BUILD INTO THE PACIFIC NW AND THE GREAT BASIN. LOOKS LIKE TONIGHT
WILL REMAIN CLEAR NORTH OF THE GOLDEN GATE AS THE NORTHERLY FLOW
DISSIPATES ANY KIND OF A MARINE LAYER. SOUTH OF THE GOLDEN GATE THERE
SHOULD STILL BE SOME LOW CLOUDS ALONG THE COAST AND INTO THE VALLEYS.
SUNDAY SHOULD SEE SOME WARMING...ESPECIALLY IN THE NORTH BAY WITH THE
OFFSHORE FLOW. THE OFFSHORE FLOW WILL SPREAD ACROSS THE DISTRICT
SUNDAY NIGHT AND MONDAY. THIS WILL RESULT IN MOSTLY CLEAR SKIES
SUNDAY NIGHT...WITH LITTLE IF ANY STRATUS AND A SUNNY AND WARM LABOR
DAY. ON LABOR DAY TEMPS ALONG THE COAST SHOULD BE IN THE 70S...WITH
80S TO LOWER 90S AROUND THE BAY...AND THE 90S INLAND. INTERIOR
SECTIONS OF MONTEREY AND SAN BENITO COUNTIES COULD TOP THE CENTURY
MARK.
THE WARM SPELL WILL BE SHORT-LIVED AS A TROUGH DEEPENS AS IT DROPS
SOUTH ALONG THE WEST COAST. TUESDAY WILL BE SIGNIFICANTLY COOLER WITH
FURTHER COOLING ON WEDNESDAY. THE MARINE LAYER SHOULD DEEPEN TO OVER
2000 FEET BY LATE TUESDAY NIGHT/WEDNESDAY MORNING FOR DRIZZLE ALONG
THE COAST. TEMPS WILL BE WELL BELOW NORMAL ONCE AGAIN. MEDIUM RANGE
MODELS KEEP THE TROUGH ALONG THE COAST RESULTING IN COOLER THAN
NORMAL TEMPS ALONG WITH STRATUS ALONG THE COAST...SURGING INTO THE
VALLEYS DURING THE NIGHT AND MORNING HOURS.
&&
.AVIATION...AS OF 4:20 PM PDT SATURDAY...NORTHERLY GRADIENT IS
INCREASING AND NOW ALMOST 6 MB FROM ACV-SFO. STRATUS IS CLEARING
ALONG THE NORTH COAST AND WITH ONLY A MODERATE ONSHORE GRADIENT
EXPECT JUST SCATTERED STRATUS AND VFR CONDITIONS FOR THE SAN
FRANCISCO BAY REGION OVERNIGHT.
.VICINITY OF KSFO...VFR CONDITIONS EXPECTED OVERNIGHT WITH
JUST SCATTERED STRATUS LATER TONIGHT. GUSTY WEST TO NORTHWEST WINDS
TO 25 KT CONTINUING THROUGH 04Z THEN DECREASING TO LESS THAN 10 KT
BY 08Z.
.KSFO BRIDGE APPROACH...SAME AS VICINITY OF KSFO.
.MRY BAY AREA TERMINALS...IFR CIGS WILL LIKELY REDEVELOP BETWEEN 01-
03Z THIS EVENING. CLEARING EXPECTED EARLIER ON SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: WJK
000
FXUS65 KPSR 042310
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
410 PM MST SAT SEP 4 2010
.UPDATE...UPDATED AVIATION SECTION.
&&
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN TO WEAKEN SUNDAY AS A LOW PRESSURE SYSTEM
PASSES TO THE NORTH...THOUGH TEMPERATURES WILL REMAIN WELL ABOVE
NORMAL. A COOLING TREND CAN BE EXPECTED MONDAY THROUGH THURSDAY AS A
DEEPER TROUGH OF LOW PRESSURE MOVES THROUGH THE WESTERN STATES. IN
FACT...SLIGHTLY BELOW NORMAL TEMPERATURES WILL PREVAIL ACROSS THE
REGION WEDNESDAY THROUGH SATURDAY. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX
THROUGH TUESDAY BEFORE DRY AIR OVERSPREADS THE REGION.
&&
.DISCUSSION...
24 HOUR TEMP TRENDS OVER SOUTH-CENTRAL ARIZONA HAD BEEN RUNNING WELL
AHEAD OF YESTERDAY BUT THIS WAS DUE LARGELY TO STRONGER MID-MORNING
WINDS AND ASSOCIATED MIXING. THE 24 HR TRENDS HAVE REVERSED FOR THE
EARLY AFTERNOON WITH TEMPS RUNNING 2-4 DEGREES COOLER AS WAS
INDICATED BY THE MORNING SOUNDINGS. 24 HOUR DECREASES ARE EVEN MORE
EVIDENT IN FAR SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA LIKELY DUE
TO THE SHALLOW BATCH OF MARINE TROPICAL AIR THAT MOVED IN THIS
MORNING. IN FACT...MAX TEMPS THERE MIGHT FALL JUST SHORT OF WARNING
CRITERIA. HOWEVER...CONDITIONS ARE STILL HOT AND HIGHS WILL STILL
LIKELY EXCEED 110. THUS WILL LET THE EXCESSIVE HEAT WARNING
CONTINUE. CONVECTION OUTSIDE OF OUR FORECAST AREA IS A LITTLE MORE
QUIET SO FAR THIS AFTERNOON BUT THERE IS STILL ENOUGH MOISTURE FOR A
SLIGHT CHANCE OF THUNDERSTORMS OVER ZONE 24.
BOTH THE NAM AND GFS SHOW LESS MOISTURE AROUND SUNDAY AS THEY DEPICT
SOMETHING OF A SOUTHWARD EBB. DESPITE THE ANTICYCLONE OVER US BEING
PUSHED EASTWARD DUE TO A TROUGH MOVING THROUGH THE NORTHWEST
STATES...ANTICIPATE LITTLE CHANGE IN TEMPERATURES. THE COOLING WILL
LAG AND BE MORE NOTICEABLE ON MONDAY. A CYCLONIC CIRCULATION AT THE
LOWER AND MID LEVELS NEAR BAJA IS ADVERTISED TO PULL SOME MOISTURE
NORTHWARD INTO OUR FORECAST AREA MONDAY AND TUESDAY AS IT SLOWLY
MOVES EASTWARD. FOR MONDAY THIS OCCURS MAINLY OVER THE LOWER DESERTS
OF OUR ARIZONA ZONES THEN SHIFTS EASTWARD TUESDAY TO THE HIGHER
TERRAIN...INCLUDING ZONE 24. FORECAST SOUNDINGS NOT SUPPORTING
ENOUGH INSTABILITY TO INTRODUCE POPS ON THE LOWER DESERTS. MADE A
SLIGHT ADJUSTMENT TO EXPAND THE AREA OF SLIGHT CHANCES OVER ZONE 24
FOR TUESDAY. MEANWHILE ANOTHER TROUGH IN THE WESTERLIES MOVES INTO
THE WESTERN STATES TUESDAY FOR SOME BREEZY CONDITIONS AND MODEST
ADDITIONAL COOLING...MORE NOTICEABLE OVER OUR WESTERN AREAS...WITH
TEMPS NEAR NORMAL.
IN THE EXTENDED...ECMWF AND GFS AGREE THAT BROAD TROUGHING WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A STRONG LOW
PRESSURE SYSTEM MOVING THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...PASSING MOSTLY TO THE NORTH BUT BRINGING IN DRY AIR TO
THE REGION. FORECAST TEMPS SHOULD LOWER TO SLIGHTLY BELOW NORMAL
WEDNESDAY THROUGH SATURDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
ISOLATED THUNDERSTORMS WILL GENERALLY REMAIN CONFINED BEYOND 60 NM
OF THE PHOENIX METRO AREA LATE THIS AFTERNOON. CHANCE FOR AN OUTFLOW
REACHING KPHX/KIWA IS EXTREMELY LOW. THUNDERSTORM IMPACTS LOOK LOW
AGAIN FOR SUNDAY.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
GENERALLY CLEAR SKIES AND LIGHT WINDS THROUGH SUNDAY AFTERNOON.
SOUTHERLY WINDS WILL INCREASE AT KBLH SUNDAY AFTERNOON AS A LOW
PRESSURE SYSTEM MOVES THROUGH THE INTERMOUNTAIN WEST. GUSTS TO 20KT
WILL BE POSSIBLE.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP
NEAR THE WEST COAST WITH COOLER WEATHER DURING THE MIDDLE OF THE
WEEK. THIS SYSTEM WILL ALSO RESULT IN BREEZY WINDS FROM THE SOUTHWEST
IN THE AFTERNOONS WITH GUSTS BETWEEN 20 AND 30 MPH TUESDAY AND
WEDNESDAY. THE AIR WILL BE DRY WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ
AVIATION...HIRSCH
FIRE WEATHER...ELLIS
000
FXUS66 KEKA 042218
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
318 PM PDT SAT SEP 4 2010
.SYNOPSIS...A WEAK COOL FRONT WILL MOVE ACROSS NORTHWEST CALIFORNIA
THIS WEEKEND...PRODUCING ROBUST NORTHERLY WINDS ALONG THE COAST
AND A COOLING TREND ACROSS THE INTERIOR.
&&
.DISCUSSION...THE UPPER LEVEL PATTERN CONSISTS OF A TROUGH MOVING
ACROSS THE PAC NW DRAGGING A WEAK COLD FRONT TOWARD NRN CA. TEMPS
TODAY ARE RUNNING 5 TO 10 DEGREES BEHIND YESTERDAYS READINGS.
PLENTY OF STRATUS ALONG THE COAST AND OVER THE WATER THIS MORNING
IS BREAKING UP THIS AFTERNOON AS NORTH WINDS CONTINUE TO
INCREASE. CLOUDS WILL RETURN TO THE COAST OVERNIGHT...ESPECIALLY
NORTH OF THE CAPE AS THE WINDS WILL HELP PILE THE CLOUDS IN AROUND
THE BAY. SHORTWAVE RIDGING MOVES OVERHEAD BEGINNING SUNDAY EVENING
AS A THERMAL TROUGH STRENGTHENS AND SHIFTS TOWARD THE COAST.
OFFSHORE WINDS ARE EXPECTED SUNDAY NIGHT AND THE FIRST HALF OF
MONDAY WITH GUSTS AS HIGH AS 30 MPH EXPECTED ACROSS THE RIDGETOPS.
HUMIDITY RECOVERIES WILL BE POOR AS A RESULT AND THIS WILL BE
ADDRESSED WITHIN THE APPROPRIATE FIRE WX PRODUCTS. ANOTHER
MANIFESTATION OF THE OFFSHORE WINDS WILL BE TO BREAK UP THE MARINE
LAYER AND PUSH IT WELL OFFSHORE. AS A RESULT...WE EXPECT LABOR DAY
TO BE A MOSTLY SUNNY DAY ALONG WITH WARMER TEMPS.
A STRONGER TROUGH DROPPING SOUTH ALONG THE WEST COAST OF CANADA WILL
BEGIN TO AFFECT OUR WEATHER ON TUESDAY...FIRST WITH SIGNIFICANT
COOLING...MAINLY ACROSS THE INTERIOR. MODELS HAVE BEEN TRACKING
THIS LOW JUST OFF THE WEST COAST...ALLOWING IT TO PICK UP A
LITTLE MORE MOISTURE AS IT HEADS FOR NRN CA...BEFORE THEN SHIFTING
EAST. WITH STRONG ONSHORE FLOW BEGINNING TUE...A FEW SHOWERS ARE A
REAL POSSIBILITY...ESPECIALLY FOCUSED ALONG THE HIGHER TERRAIN.
THE COLD POOL MOVES OVER NW CA TUE NIGHT PROVIDING OUR BEST SHOT
FOR A FEW LIGHT SHOWERS REGION WIDE. WEDNESDAY WILL BE THE
CHILLIEST DAY ACROSS THE INTERIOR WITH TEMPS STRUGGLING TO ACHIEVE
THE MID 70S. AFTER THE TROUGH MOVES THROUGH BY LATE WED...ECMWF
AND GFS HAVE A FLAT RIDGE BUILDING WITH A COUPLE OF MINOR
SHORTWAVES MOVING INTO THE PACIFIC NORTHWEST. STRONG WARMING IS
UNLIKELY AND EXPECT DRY WEATHER OVERALL. JCA
&&
.AVIATION...STRATUS WILL QUICKLY BUILD ALONG THE COAST THIS
EVENING...BRINGING IFR/LIFR DUE TO CEILINGS AND VISIBILITIES. EXPECT
VFR TO PREVAIL INLAND...THOUGH SOME STRATUS MAY PROPAGATE INTO THE
VALLEYS ALONG THE IMMEDIATE COAST. STROZ
&&
.MARINE...NO CHANGES MADE TO ANY OF THE CURRENT WARNINGS. NORTH
WINDS WILL CONTINUE TO INCREASE TONIGHT INTO SUNDAY AS THE SURFACE
PRESSURE GRADIENT TIGHTENS. AS A RESULT, SUSTAINED WINDS OF 25 TO 35
KT WITH GUSTS UP TO 45 KT ARE EXPECTED OVER THE OUTER WATERS THROUGH
MONDAY. THE STRONGEST WINDS ARE EXPECTED SUNDAY AFTERNOON. ALONG
WITH THE WINDS, STEEP SHORT PERIOD SEAS WILL BUILD ACROSS THE OUTER
WATERS TO NEAR 15 FT AT 8 SECONDS. THE HAZARDOUS SEAS WILL PROPAGATE
INTO THE SOUTHERN INNER WATERS TOMORROW, SO KEPT THAT WARNING GOING.
THE NORTHERN INNER WATERS WILL REMAIN UNDER A SCA DUE TO WINDS AND
SEAS. THE PRESSURE GRADIENT WILL BEGIN TO EASE ON TUESDAY, ALLOWING
WINDS TO FALL AND SEAS TO SUBSIDE. STROZ
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY PZZ450-455.
HAZARDOUS SEAS WARNING PZZ455.
GALE AND HAZARDOUS SEAS WARNING PZZ470-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS65 KPSR 042208
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
310 PM MST SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN TO WEAKEN SUNDAY AS A LOW PRESSURE SYSTEM
PASSES TO THE NORTH...THOUGH TEMPERATURES WILL REMAIN WELL ABOVE
NORMAL. A COOLING TREND CAN BE EXPECTED MONDAY THROUGH THURSDAY AS A
DEEPER TROUGH OF LOW PRESSURE MOVES THROUGH THE WESTERN STATES. IN
FACT...SLIGHTLY BELOW NORMAL TEMPERATURES WILL PREVAIL ACROSS THE
REGION WEDNESDAY THROUGH SATURDAY. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX
THROUGH TUESDAY BEFORE DRY AIR OVERSPREADS THE REGION.
&&
.DISCUSSION...
24 HOUR TEMP TRENDS OVER SOUTH-CENTRAL ARIZONA HAD BEEN RUNNING WELL
AHEAD OF YESTERDAY BUT THIS WAS DUE LARGELY TO STRONGER MID-MORNING
WINDS AND ASSOCIATED MIXING. THE 24 HR TRENDS HAVE REVERSED FOR THE
EARLY AFTERNOON WITH TEMPS RUNNING 2-4 DEGREES COOLER AS WAS
INDICATED BY THE MORNING SOUNDINGS. 24 HOUR DECREASES ARE EVEN MORE
EVIDENT IN FAR SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA LIKELY DUE
TO THE SHALLOW BATCH OF MARINE TROPICAL AIR THAT MOVED IN THIS
MORNING. IN FACT...MAX TEMPS THERE MIGHT FALL JUST SHORT OF WARNING
CRITERIA. HOWEVER...CONDITIONS ARE STILL HOT AND HIGHS WILL STILL
LIKELY EXCEED 110. THUS WILL LET THE EXCESSIVE HEAT WARNING
CONTINUE. CONVECTION OUTSIDE OF OUR FORECAST AREA IS A LITTLE MORE
QUIET SO FAR THIS AFTERNOON BUT THERE IS STILL ENOUGH MOISTURE FOR A
SLIGHT CHANCE OF THUNDERSTORMS OVER ZONE 24.
BOTH THE NAM AND GFS SHOW LESS MOISTURE AROUND SUNDAY AS THEY DEPICT
SOMETHING OF A SOUTHWARD EBB. DESPITE THE ANTICYCLONE OVER US BEING
PUSHED EASTWARD DUE TO A TROUGH MOVING THROUGH THE NORTHWEST
STATES...ANTICIPATE LITTLE CHANGE IN TEMPERATURES. THE COOLING WILL
LAG AND BE MORE NOTICEABLE ON MONDAY. A CYCLONIC CIRCULATION AT THE
LOWER AND MID LEVELS NEAR BAJA IS ADVERTISED TO PULL SOME MOISTURE
NORTHWARD INTO OUR FORECAST AREA MONDAY AND TUESDAY AS IT SLOWLY
MOVES EASTWARD. FOR MONDAY THIS OCCURS MAINLY OVER THE LOWER DESERTS
OF OUR ARIZONA ZONES THEN SHIFTS EASTWARD TUESDAY TO THE HIGHER
TERRAIN...INCLUDING ZONE 24. FORECAST SOUNDINGS NOT SUPPORTING
ENOUGH INSTABILITY TO INTRODUCE POPS ON THE LOWER DESERTS. MADE A
SLIGHT ADJUSTMENT TO EXPAND THE AREA OF SLIGHT CHANCES OVER ZONE 24
FOR TUESDAY. MEANWHILE ANOTHER TROUGH IN THE WESTERLIES MOVES INTO
THE WESTERN STATES TUESDAY FOR SOME BREEZY CONDITIONS AND MODEST
ADDITIONAL COOLING...MORE NOTICEABLE OVER OUR WESTERN AREAS...WITH
TEMPS NEAR NORMAL.
IN THE EXTENDED...ECMWF AND GFS AGREE THAT BROAD TROUGHING WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A STRONG LOW
PRESSURE SYSTEM MOVING THROUGH THE INTERIOR WEST WEDNESDAY AND
THURSDAY...PASSING MOSTLY TO THE NORTH BUT BRINGING IN DRY AIR TO
THE REGION. FORECAST TEMPS SHOULD LOWER TO SLIGHTLY BELOW NORMAL
WEDNESDAY THROUGH SATURDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
WINDS FROM THE SOUTHEAST ARE EXPECTED TO BECOME LIGHT AND VARIABLE
FAVORING FROM THE NORTHWEST LATE THIS AFTERNOON AND EARLY THIS
EVENING...THEN FROM THE EAST LATE THIS EVENING THROUGH SUNDAY
MORNING. A FEW CLOUDS NEAR 12 THOUSAND FEET ARE EXPECTED...THEN
BECOMING CLEAR BY LATE THIS EVENING THROUGH SUNDAY. ISOLATED
THUNDERSTORMS THIS AFTERNOON AND EARLY THIS EVENING ARE EXPECTED TO
STAY OVER THE HIGHER TERRAIN WELL NORTHEAST AND EAST OF THE GREATER
PHOENIX AREA.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...CLEAR
SKIES AND LIGHT DIURNAL WINDS ARE EXPECTED THROUGH SUNDAY...MOSTLY
FROM THE SOUTH AT KBLH.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP
NEAR THE WEST COAST WITH COOLER WEATHER DURING THE MIDDLE OF THE
WEEK. THIS SYSTEM WILL ALSO RESULT IN BREEZY WINDS FROM THE SOUTHWEST
IN THE AFTERNOONS WITH GUSTS BETWEEN 20 AND 30 MPH TUESDAY AND
WEDNESDAY. THE AIR WILL BE DRY WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ
AVIATION...ELLIS
FIRE WEATHER...ELLIS
000
FXUS65 KREV 042154
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
254 PM PDT SAT SEP 4 2010
.SHORT TERM...
THE MAIN ITEMS OF CONCERN IN THE SHORT TERM (OUTSIDE OF FIRE WEATHER)
ARE EASTERLY WINDS ON LAKE TAHOE SUNDAY NIGHT AND MONDAY MORNING AS
WELL AS COLDER VALLEY LOW TEMPS MONDAY AND TUESDAY MORNINGS.
A COLD FRONT CURRENTLY BISECTING OREGON IN A NORTHEAST TO SOUTHWEST
FASHION WILL PUSH INTO THE FAR NORTHERN CWA LATE TONIGHT BEFORE
DRIVING THROUGH THE REST OF THE CWA SUNDAY AND SUNDAY NIGHT AS AN
UPPER LOW SLIDES THROUGH THE FAR NORTHWEST CONUS. AHEAD OF THE
FRONT...GUSTY WINDS AND WELL ABOVE AVERAGE TEMPERATURES PREVAIL
THIS AFTERNOON. HIGHS WILL DROP SOME 5 TO 15 DEGREES (HIGHEST NORTH
AND EAST) FROM THIS AFTERNOON TO SUNDAY AFTERNOON AS THE FRONT DRIVES
THROUGH.
AS MENTIONED AT THE BEGINNING OF THIS DISCUSSION...EASTERLY WINDS
ON LAKE TAHOE SUNDAY NIGHT AND MONDAY MORNING ARE A CONCERN. MODEL
SOUNDINGS ARE SHOWING 15-20 KTS OF EASTERLY FLOW SUNDAY NIGHT ALONG
WITH COLD AIR ADVECTION AT AND BELOW 700 MB AND AT LEAST 8 MB OF
SURFACE GRADIENT BETWEEN RENO AND SACRAMENTO BY 12Z MONDAY. AS IT
IS A MAJOR HOLIDAY WEEKEND FOR OUTDOOR ACTIVITIES...I HAVE DECIDED
TO PUT OUT A LAKE WIND ADVISORY AND WEATHER GRAPHIC (SEE OUR WEB
PAGE) TO GET THE WORD OUT EXTRA EARLY.
MONDAY LOOKS LIKE THE COLDEST DAY OF THE SHORT TERM FOR MOST AREAS
AS EASTERLY FLOW INHIBITS MIXING AND KEEPS THE LOW LEVEL THERMAL
TROUGH WEST OF THE CREST. I HAVE GONE CONSIDERABLY BELOW GFS MOS
GUIDANCE (CLOSE TO THE NAM MOS) FOR HIGHS MONDAY AS IT USUALLY
OVERDOES HIGHS IN EASTERLY FLOW. AS FAR AS LOWS MONDAY MORNING AND
TUESDAY MORNING...VERY DRY AIR MOVES IN BEHIND SUNDAY`S COLD FRONT.
THUSLY...I EXPECT LOWS TO BOTTOM OUT IN THE 30S FOR MANY VALLEYS
AND UPPER 20S TO LOWER 30S FOR THE SIERRA VALLEYS AND MANY OF THE
LOWER VALLEYS OF LASSEN...PLUMAS...AND SIERRA COUNTIES. SEE OUR
SPECIAL WEATHER STATEMENT FOR OUR CONCERNS WITH COLD TEMPS MONDAY
MORNING. LOWS MONDAY NIGHT COULD BE ALMOST AS COLD FOR MANY VALLEYS
AS DRY AIR AND LIGHT WINDS PREVAIL.
TUESDAY AND TUESDAY NIGHT...AN UPPER LOW WILL DROP DOWN THE PACIFIC
NORTHWEST COAST AND BRING A SLIGHT CHANCE OF SHOWERS INTO THE NORTHERN
AND NORTHWESTERN CWA. HIGHS WILL JUMP BACK UP TO AVERAGE TO A BIT
ABOVE AVERAGE TUESDAY WITH BETTER MIXING AHEAD OF THE INCOMING LOW.
SNYDER
.LONG TERM...WEDNESDAY THROUGH SATURDAY...
UPPER TROUGH WILL DEEPEN AND MOVE INTO THE PACIFIC NORTHWEST AND
NORTHERN CALIFORNIA WEDNESDAY. THE EC IS DEEPER...COLDER... AND
ABOUT 12 HOURS SLOWER THAN THE GFS AND WAS FOLLOWED IN PREVIOUS
FORECAST. THAT THINKING AND TIMING WILL BE RETAINED FOR THIS
FORECAST CYCLE.
WEDNESDAY WILL BE WINDY AND MILD WITH THE JET EXTENDING FROM THE BAY
AREA ACROSS TAHOE INTO NORTHWEST NEVADA AND A STRONG EAST TO WEST
THERMAL GRADIENT FROM NORTHERN CA INTO WESTERN NEVADA. KEPT THE
CHANCE OF SHOWERS AND SLIGHT CHANCE OF THUNDER PORTIONS OF WESTERN
NEVADA AHEAD OF THE FRONT. THE TROUGH SWINGS INLAND WEDNESDAY
NIGHT...WITH AN UPPER LOW FROM TAHOE NORTH ALONG THE CA/NV BORDER.
THIS WILL PUSH THE COLD FRONT THROUGH WESTERN NEVADA OVERNIGHT WITH
WIDESPREAD SHOWERS ACROSS NORTHEAST CA...THE SIERRA...INTO WESTERN
NV. THE EC BRINGS 700MB TEMPERATURES OF -4C FROM TAHOE NORTH SO
COULD SEE SOME HIGH LEVEL...ABOVE 8000 FT... LIGHT SNOW WEDNESDAY
NIGHT AND EARLY THURSDAY.
THURSDAY WILL BE THE COOLEST DAY WITH WIDESPREAD SHOWERS SIMILAR TO
WHAT WE SAW LAST SUNDAY AUGUST 29. CURRENT HIGH TEMPERATURES ARE
FORECAST TO REMAIN IN THE 60S FOR WESTERN NV...NEARLY 10 DEGREES
LOWER THAN MOS GUIDANCE.
BY FRIDAY INTO NEXT WEEKEND THE PATTERN MODERATES WITH FALL LIKE
WEATHER ON TAP AS TEMPERATURES WARM INTO THE 70S WITH NEAR 80 IN
SOME WESTERN VALLEYS BY THE WEEKEND. JAH
&&
.AVIATION...
VFR CONDITIONS ALL TAF SITES. AN UPPER TROF WILL MOVE INTO THE
PACNW TONIGHT AND ACROSS NORTHERN NEVADA SUNDAY PUSHING A COLD FRONT
THROUGH KRNO-KNFL SUNDAY AFTERNOON. RIDGE GUSTS WILL INCREASE TO
45KT TONIGHT AND DIMINISH SUNDAY AFTERNOON. EXPECT AFTERNOON AND
EVENING ZEPHYR WINDS TO THE LEE OF THE SIERRA WITH OCCASIONAL GUSTS
TO 25KT AT KRNO UNTIL 04Z...AND 20KT-25KT AT KTRK/KTVL UNTIL 02Z. JAH
&&
.FIRE WEATHER...
WITH LOCAL GUSTS UP TO 35 MPH THIS EVENING...A FEW OF THE MORE WIND
PRONE SITES IN PARTS OF WRN NV NORTH OF HIGHWAY 50 COULD REACH LOW
END RED FLAG CRITERIA...BUT OVERALL A WIDESPREAD WIND EVENT IS NOT
EXPECTED SO THE CURRENT HEADLINE WILL REMAIN IN PLACE TO COVER THIS
ONGOING TROF AND FRONT PASSAGE. MID SLOPE AND LOWER ELEVATION HUMIDITY
RECOVERY WILL BE POOR TONIGHT ESPECIALLY FROM I-80 SOUTHWARD...AND
DOES NOT SHOW MUCH IMPROVEMENT FOR THE FOLLOWING COUPLE OF NIGHTS
ACROSS ALL AREAS.
SUNDAY WILL BE DRY AGAIN ACROSS THE REGION WITH POST FRONTAL WINDS
FROM THE NORTHWEST AND NORTH. GUSTS SHOULD RANGE FROM 25 TO 30 MPH
ACROSS MOST OF THE REGION...NOT SUFFICIENT FOR RED FLAG CONDITIONS
BUT STILL MENTIONED IN THE CURRENT HEADLINE.
NEXT DAY OF CONCERN WILL BE TUESDAY AS SOUTHWEST FLOW INCREASES
AHEAD OF A STRONGER TROF DROPPING INTO THE NWRN US. SOME UNCERTAINTY
STILL EXISTS IN TIMING AS PEAK WINDS MAY BE DELAYED UNTIL TUES
NIGHT. IF THIS SYSTEM STILL SHOWS THIS TRACK AND STRENGTH WITH
UPCOMING MODEL RUNS...THEN A WATCH COULD BE ISSUED FOR PORTIONS OF
THE REGION BY SUNDAY AFTERNOON. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 10 PM SUNDAY TO 10 AM PDT MONDAY FOR
LAKE TAHOE IN NVZ002.
CA...LAKE WIND ADVISORY FROM 10 PM SUNDAY TO 10 AM PDT MONDAY FOR
LAKE TAHOE IN CAZ072.
&&
$$
HTTP://WEATHER.GOV/RENO
000
FXUS66 KHNX 042149
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
249 PM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL CONTINUE TO BUILD OVER CENTRAL CALIFORNIA.
STRONG WARMING WILL SEND TEMPERATURES SOME 10 TO 15 DEGREES ABOVE
AVERAGE TODAY. AN UPPER-LEVEL TROUGH WILL BRING COOLER TEMPERATURES
FOR LABOR DAY AND THE FIRST PART OF NEXT WEEK.
&&
.DISCUSSION...
CLEAR DRY CONDITIONS ACROSS THE REGION WITH TEMPERATURES A BIT
COOLER IN MOST LOCATIONS. AN UPPER TROUGH OVER THE PACIFIC NW
WILL MOVE SE REACHING THE GREAT BASIN SUNDAY. THIS WILL WEAKEN THE
UPPER RIDGE OVER THE SW BRINGING A COOLING TREND ACROSS THE
REGION. HOWEVER THE COOLING MAY NOT BE SIGNIFICANT UNTIL TUESDAY
AS THE COLDER AIR MAY REMAIN IN THE THE GREAT BASIN EAST OF THE
SIERRA. THE BEST COOLING MAY BE TOWARDS MOJAVE SUNDAY AS STRONGER
ONSHORE GRADIENTS BRINGS COOLER MARINE AIR ALONG WITH STRONGER
GUSTY WINDS. LITTLE MOISTURE AVAILABLE FOR ANY THREAT OF
PRECIPITATION. PRESSURE GRADIENTS INCREASE ALONG THE CENTRAL
COAST TUESDAY AFTERNOON AS A STRONGER UPPER TROUGH MOVES DOWN THE
PAC NW COAST INTO NORTH CALIFORNIA. THE STRONGER GRADIENTS AND
ONSHORE FLOW WILL BRING COOL MARINE AIR INTO THE INTERIOR
CALIFORNIA TUESDAY AFTERNOON. STRONG GUSTY WINDS WILL LIKELY OCCUR
THROUGH THE COASTAL MOUNTAINS PASSES OF THE VALLEY THROUGH TUESDAY
NIGHT. THE UPPER TROUGH AXIS WILL PUSH THROUGH CENTRAL CALIFORNIA
WEDNESDAY. BREEZY CONDITIONS SHOULD DEVELOP IN THE SAN JOAQUIN
VALLEY AS A 90KT JET ALIGNS WITH THE ONSHORE GRADIENTS. EXPECT
THE STRONGER GUSTY WINDS TO OCCUR THROUGH BELOW MOUNTAIN PASSES OF
KERN COUNTY. SOME LIGHT PRECIPITATION MAY BE POSSIBLE OVER THE
SIERRA WEDNESDAY INTO THURSDAY MORNING. GFS MODEL IS TRENDING
DRIER THAN THE ECWM DURING THE MID WEEK SYSTEM. A COLDER AIRMASS
WILL RESULT IN WELL BELOW NORMAL TEMPERATURES WEDNESDAY AND
THURSDAY. TEMPERATURES START TO WARM FRIDAY BUT A WEST FLOW ALOFT
MAY MAINTAIN BELOW SEASONAL TEMPERATURE FOR THE REMAINDER OF THE
WEEK.
&&
.AVIATION...
AS THE BASE OF THE U/L TROUGH BRUSHES BY SUN AFTN AND EVNG SOME
GUSTY WINDS WILL BE POSSIBLE ACROSS THE SIERRA RIDGETOPS AND THROUGH
AND BELOW KERN COUNTY PASSES...GUSTS UP TO 40 KTS WILL BE POSSIBLE
THERE. OTHERWISE...VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL
CALIFORNIA INTERIOR THROUGH 00Z MONDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BROTHERTON
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KMTR 042145
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
245 PM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 2:30 PM PDT SATURDAY...TODAY ENDED UP BEING
SIGNIFICANTLY COOLER THAN WAS EXPECTED. EARLIER THIS AFTERNOON
UPDATED THE TEMP GRIDS FOR TODAY...BUT IT STILL WAS COOLER THAN
EXPECTED. HOWEVER...SATL IMAGERY IS SHOWING A CHANGE IN THE WEATHER
FOR THE DISTRICT AS STRATUS HAS BEEN DECREASING OVER NORTHWEST CA AS
A SFC NORTHERLY FLOW STRENGTHENS. THIS CAN BE SEEN IN THE GRADIENT
PICTURE WHICH SHOWS THE ARCATA-SFO GRADIENT IS NORTHERLY AT 4.9 MB...
AN INCREASE OF MORE THAN 2 MB SINCE THE MORNING. THE SFO-SAC GRADIENT
IS ONSHORE AT 2.4 MB.
AS A SHORTWAVE CONTINUES TO MOVE INTO THE ROCKIES A SFC HIGH WILL
BUILD INTO THE PACIFIC NW AND THE GREAT BASIN. LOOKS LIKE TONIGHT
WILL REMAIN CLEAR NORTH OF THE GOLDEN GATE AS THE NORTHERLY FLOW
DISSIPATES ANY KIND OF A MARINE LAYER. SOUTH OF THE GOLDEN GATE THERE
SHOULD STILL BE SOME LOW CLOUDS ALONG THE COAST AND INTO THE VALLEYS.
SUNDAY SHOULD SEE SOME WARMING...ESPECIALLY IN THE NORTH BAY WITH THE
OFFSHORE FLOW. THE OFFSHORE FLOW WILL SPREAD ACROSS THE DISTRICT
SUNDAY NIGHT AND MONDAY. THIS WILL RESULT IN MOSTLY CLEAR SKIES
SUNDAY NIGHT...WITH LITTLE IF ANY STRATUS AND A SUNNY AND WARM LABOR
DAY. ON LABOR DAY TEMPS ALONG THE COAST SHOULD BE IN THE 70S...WITH
80S TO LOWER 90S AROUND THE BAY...AND THE 90S INLAND. INTERIOR
SECTIONS OF MONTEREY AND SAN BENITO COUNTIES COULD TOP THE CENTURY
MARK.
THE WARM SPELL WILL BE SHORT-LIVED AS A TROUGH DEEPENS AS IT DROPS
SOUTH ALONG THE WEST COAST. TUESDAY WILL BE SIGNIFICANTLY COOLER WITH
FURTHER COOLING ON WEDNESDAY. THE MARINE LAYER SHOULD DEEPEN TO OVER
2000 FEET BY LATE TUESDAY NIGHT/WEDNESDAY MORNING FOR DRIZZLE ALONG
THE COAST. TEMPS WILL BE WELL BELOW NORMAL ONCE AGAIN. MEDIUM RANGE
MODELS KEEP THE TROUGH ALONG THE COAST RESULTING IN COOLER THAN
NORMAL TEMPS ALONG WITH STRATUS ALONG THE COAST...SURGING INTO THE
VALLEYS DURING THE NIGHT AND MORNING HOURS.
&&
.AVIATION...AS OF 10:35 AM PDT SATURDAY...SKIES WERE RAPIDLY CLEARING
INLAND ON SATURDAY MORNING...AND EXPECT VFR CONDITIONS AT ALL
TERMINALS BY 19Z. THE MARINE LAYER WILL REMAIN ABOUT 1500 FEET DEEP
THROUGH SUNDAY MORNING. HOWEVER...NORTHERLY SURFACE GRADIENTS WILL
INCREASE...WHICH WILL DELAY INLAND DEVELOPMENT OF LOW CIGS IN THE SF
BAY AREA UNTIL LATE TONIGHT...WELL PAST THE EVENING RUSH. IFR CIGS
WILL DEVELOP NEAR MONTEREY BAY BY 02-03Z THIS EVENING. INCREASING
NORTHERLY FLOW ON SUNDAY WILL RESULT IN EARLIER CLEARING WITH VFR
CONDITIONS EXPECTED IN MOST AREAS BY 17Z SUNDAY MORNING. MODERATE
WEST WINDS ARE FORECAST FROM MID AFTERNOON THROUGH EARLY EVENING.
.VICINITY OF KSFO...VFR CONDITIONS THROUGH THE EVENING. WEST TO
NORTHWEST WINDS INCREASING TO 17G23KT BY 23Z AND CONTINUING THROUGH
04Z. IFR CIGS WILL LIKELY DEVELOP LATE TONIGHT AROUND 12Z...BUT THEN
CLEAR BY 17Z ON SUNDAY MORNING.
.KSFO BRIDGE APPROACH...VFR CONDITIONS DEVELOPING BY 18Z AND
CONTINUING THROUGH THE EVENING WITH IFR CIGS NOT LIKELY UNTIL 12Z
LATE TONIGHT. CLEARING EXPECTED BY 17Z SUNDAY MORNING.
.MRY BAY AREA TERMINALS...IFR CIGS THRU 19Z. VFR CONDITIONS EXPECTED
FROM MIDDAY THROUGH THE AFTERNOON. IFR CIGS WILL LIKELY REDEVELOP
BETWEEN 01-03Z EARLY THIS EVENING. CLEARING EXPECTED EARLIER ON
SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: DYKEMA
000
FXUS66 KSTO 042129
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
230 PM PDT SAT SEP 4 2010
.DISCUSSION...
THE DELTA BREEZE HAS LIGHTENED UP THIS AFTERNOON AND WILL ALLOW
TEMPERATURES TO WARM INTO THE MID 90S TODAY AROUND SACRAMENTO TO THE
UPPER 90S WELL INLAND. THE DELTA BREEZE SHOULD INCREASE LATER THIS
AFTERNOON AND EVENING. LOW CLOUDS STILL LOCALLY INTO THE BAY WILL
RETURN EARLIER TONIGHT. THIS WILL ALLOW FOR MUCH BETTER COOLING THIS
EVENING THAN THE LAST FEW NIGHTS.
THE TAIL OF A WEAK LOW PRESSURE AREA WILL MOVE THROUGH THE REGION
TONIGHT. THE LOW WILL HELP TO COOL TEMPERATURES A LITTLE IN THE
VALLEY BUT MORE NOTICEABLE IN THE MOUNTAINS FOR SUNDAY. SUNDAY WILL
GENERALLY BE THE COOLEST DAY THIS WEEKEND FOR ALMOST ALL AREAS
EXCEPT PERHAPS THE DELTA WHICH MAY HAVE ITS COOLEST DAY TODAY.
NORTHERLY WINDS WILL ALSO DEVELOP ON SUNDAY AND WILL LIMIT THE COOL
DOWN. CONDITIONS LOOK LIKE THEY MAY BE BREEZY OVER THE NORTH END OF
THE VALLY IN THE AFTERNOON. GUSTY WINDS LOOKS TO DEVELOP A LITTLE
STRONGER OVER THE NORTHERN MOUNTAINS AND COASTAL RANGE SUNDAY NIGHT
WITH SOME GUSTS BETWEEN 30 AND 40 MPH OVER THE FAVORED RIDGES AND
THOUGH NORTH TO NORTHEAST FACING CANYONS. THE FLOW WILL REVERSE
ITSELF MONDAY NIGHT INTO TUESDAY MORNING AS A STRONGER LOW PRESSURE
AREA APPROACHES THE REGION AND GREATER SYNOPTIC COOLING OCCURS AND A
STRONGER DELTA BREEZE DEVELOPS AFTER SLACKENING FOR A COUPLE OF DAYS.
.EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)...A STRONG UPPER
LEVEL LOW WILL DROP DOWN FROM THE GULF OF ALASKA AND IMPACT THE
REGION WEDNESDAY. THIS LOW WILL IMPACT THE FORECAST AREA WITH COOLER
TEMPS AND A CHANCE OF SHOWERS TO THE MOUNTAINS AND NORTHERN
SACRAMENTO VALLEY IN ADDITION TO A CHANCE OF T-STORMS WEDNESDAY
AFTERNOON OVER THE SIERRA CASCADES NORTHWARD OF QUINCY AND WESTWARD
TOWARD TRINITY COUNTY TO INCLUDE THE NORTHERN SACRAMENTO VALLEY.
HIGHS ON WEDNESDAY COULD RUN 10 TO 15 DEG F BELOW TUESDAY`S READINGS
WHICH WILL LIKELY BE 10 TO 15 DEGREES BELOW AVERAGE FOR THIS TIME OF
YEAR. CURRENT MEDIUM RANGE MODEL PROGS SHIFT THE UPPER TROUGH EAST
INTO THE GREAT BASIN EARLY THURSDAY AND REPLACE THE PATTERN WITH A
WEAK ZONAL FLOW WITH BENIGN WEATHER. JCLAPP
&&
.AVIATION...
VFR CONDS NEXT 24 HOURS. SW-W SFC WINDS ACROSS MTNS THIS AFTN
REPLACED BY NORTHERLY WINDS TONIGHT AND SUN OVER NRN MTNS AND NRN
SAC VALLEY DUE TO TIGHTENING OFFSHORE PRESSURE GRADIENT. EXPECT
GUSTY W-NW WINDS ALOFT. JCLAPP
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS65 KPSR 042050
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
150 PM MST SAT SEP 4 2010
.UPDATE...
UPDATED AVIATION AND FIRE WEATHER SECTIONS.
&&
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL BRING A CONTINUATION OF WELL ABOVE
NORMAL DAYTIME HIGH TEMPERATURES THROUGH SUNDAY. EXPECT TEMPERATURES
TO DRIFT LOWER NEXT WEEK AS THE HIGH PRESSURE SYSTEM MOVES OFF TO
THE EAST...WHILE A COUPLE OF RATHER STRONG LOW PRESSURE SYSTEMS MOVE
THROUGH THE INTERMOUNTAIN WEST. IN FACT...SLIGHTLY BELOW NORMAL
TEMPERATURES WILL PREVAIL ACROSS THE REGION WEDNESDAY THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF ISOLATED THUNDERSTORMS
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX TODAY THROUGH
NEXT TUESDAY.
&&
.DISCUSSION...
AZ SOUNDINGS THIS MORNING SHOW A NOTABLE GAINS IN MOISTURE FROM
YESTERDAY MORNING...AT LEAST PART OF WHICH WAS REALIZED DURING THE
DAY YESTERDAY. ACCORDINGLY...THE TEMPERATURE PROFILES IN THE LOWER
LEVELS ARE NOT AS WARM. THUS TEMPS OVER SOUTH-CENTRAL ARIZONA WILL
NOT BE QUITE AS HOT...AS IS FORECAST. ALOFT HOWEVER THERE HAS BEEN
WARMING ABOVE 500 MB AND THIS WILL SERVE TO REDUCE INSTABILITY
DESPITE THE MOISTURE GAIN...THOUGH AN ISOLATED THUNDERSTORM IS STILL
POSSIBLE OVER ZONE 24 AND MORE LIKELY OVER THE WHITE MOUNTAINS AND
PORTIONS OF SOUTHEAST ARIZONA. WITH NO SOUNDING AVAILABLE FROM THE
YUMA AREA ON WEEKENDS...THE TRENDS IN THE MOISTURE PROFILE DO NOT
NECESSARILY APPLY TO FAR WESTERN ARIZONA AND SOUTHEAST CALIFORNIA.
GPS IPW SENSORS SUGGEST THAT THEY DONT BECAUSE PRECIPITABLE WATER
VALUES ARE LOWER DESPITE THE GULF SURGE EVIDENT AT YUMA. RADAR WIND
PROFILE SHOWS THIS AS BEING SHALLOW...AND WEAKENING...AS WOULD BE
EXPECTED FROM AN MCS OUTLFOW TYPE OF SURGE. RUC FORECAST SOUNDING
REFLECTS THIS SURGE AND SHOWS IT BEING QUITE SHALLOW...MAYBE TOO
SHALLOW. NET EFFECT WILL BE SOME SLIGHT COOLING...MAINLY IN THE
SOUTHERN PORTIONS OF THE LOWER COLORADO RIVER VALLEY...BUT NOT
ENOUGH TO CANCEL THE EXCESSIVE HEAT WARNING.
12Z MODELS CONTINUE TO SHOW THE ANTICYCLONE CENTERED OVER SOUTHERN
CALIFORNIA WEAKENING AND SHIFTING EASTWARD SUNDAY AS A TROUGH OVER
WESTERN CANADA AND THE PACIFIC NORTHWEST MOVES INLAND AND DEEPENS.
MORE LATER.
PREVIOUS DISCUSSION...
UPPER LEVEL HIGH PRESSURE THAT BROUGHT EXCESSIVE HEAT TO THE LOWER
DESERT ON FRIDAY WAS CENTERED JUST NORTHWEST OF LOS ANGELES THIS
MORNING...WITH RIDGE AXIS EXTENDING EAST ACROSS CENTRAL ARIZONA.
CENTER OF THE HIGH WILL MIGRATE SLOWLY EAST TODAY AND TONIGHT...THEN
WEAKEN SLOWLY AND MOVES TO SOUTHERN NEW MEXICO BY SUNDAY EVENING. AS
SUCH...WELL ABOVE NORMAL DAYTIME HIGHS WILL PERSIST THROUGH SUNDAY.
FORECAST SOUNDINGS INDICATE BOUNDARY LAYER TEMP WILL BE...ON
AVERAGE...1-3 F LOWER OVER THE LOWER DESERT TODAY COMPARED TO
FRIDAY...AND 1-2 F LOWER SUNDAY COMPARED TO TODAY. EXCESSIVE HEAT
WARNING...DRIVEN BY EXPECTED MAX TEMPS...WILL REMAIN IN EFFECT OVER
FAR SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA TODAY. AS EXPECTED...
ATMOSPHERE DID MOISTEN UP ACROSS SOUTH-CENTRAL AZ COMMENCING FRIDAY
AFTERNOON...AND SOME MOIST ADVECTION WILL OCCUR ACROSS WESTERN AZ
AND EXTREME SOUTHEAST CALIFORNIA TODAY. STILL...SFC DEW POINTS WILL
BE BELOW CLIMO...AND THAT...COMBINED WITH EXPECTED MID-LEVEL
WARMING...RESULTS IN DESERT SOUNDINGS PRETTY MUCH DEVOID OF CAPE.
CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGHER TERRAIN EAST OF
PHOENIX TODAY THROUGH LABOR DAY...BUT THATS ABOUT IT. RATHER STRONG
TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE INTERMOUNTAIN WEST...
MAINLY TO OUR NORTH...LATE SUNDAY INTO LABOR DAY...WHILE UPPER HIGH
MOVES WELL OFF TO OUR SOUTHEAST. AS RIDGE LOSES ITS GRIP ON THE
SOUTHWEST UNITED STATES...A COOLING TREND WILL COMMENCE...WITH LABOR
DAY HIGH TEMPS 4-6 DEGREES LOWER THAN WHAT OCCURS SUNDAY (EVEN
SO...MAX TEMPS LABOR DAY WILL BE A FEW DEGREES ABOVE CLIMO).
IN EXTENDED...ECMWF AND GFS AGREE THAT SOUTHWESTERLY FLOW WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A RATHER STRONG
TROUGH OF LOW PRESSURE FORECAST TO DEVELOP ALONG OR NEAR THE PACIFIC
COAST...THEN MOVE SLOWLY EAST ACROSS THE INTERMOUNTAIN WEST LATER IN
THE WEEK. FORECAST TEMPS SHOULD BE NEAR NORMAL TUESDAY...BUT LOWER
TO SLIGHTLY BELOW NORMAL THE REST OF THE WORK WEEK. IN ADVANCE OF
THE STRONG TROUGH...A WEAK WEATHER DISTURBANCE IS FORECAST TO BE
EJECTED EAST ACROSS SOUTHERN AZ/SONORA MEXICO ON TUESDAY...AND THIS
SYSTEM MAY TAP INTO ENOUGH MOISTURE TO INCREASE THE CHANCE FOR A
THUNDERSTORM MAINLY OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
WINDS FROM THE SOUTHEAST ARE EXPECTED TO BECOME LIGHT AND VARIABLE
FAVORING FROM THE NORTHWEST LATE THIS AFTERNOON AND EARLY THIS
EVENING...THEN FROM THE EAST LATE THIS EVENING THROUGH SUNDAY
MORNING. A FEW CLOUDS NEAR 12 THOUSAND FEET ARE EXPECTED...THEN
BECOMING CLEAR BY LATE THIS EVENING THROUGH SUNDAY. ISOLATED
THUNDERSTORMS THIS AFTERNOON AND EARLY THIS EVENING ARE EXPECTED TO
STAY OVER THE HIGHER TERRAIN WELL NORTHEAST AND EAST OF THE GREATER
PHOENIX AREA.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...CLEAR
SKIES AND LIGHT DIURNAL WINDS ARE EXPECTED THROUGH SUNDAY...MOSTLY
FROM THE SOUTH AT KBLH.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
LOW PRESSURE ALOFT FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP
NEAR THE WEST COAST WITH COOLER WEATHER DURING THE MIDDLE OF THE
WEEK. THIS SYSTEM WILL ALSO RESULT IN BREEZY WINDS FROM THE SOUTHWEST
IN THE AFTERNOONS WITH GUSTS BETWEEN 20 AND 30 MPH TUESDAY AND
WEDNESDAY. THE AIR WILL BE DRY WITH MINIMUM AFTERNOON RELATIVE
HUMIDITY BELOW 15 PERCENT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ/DG
AVIATION...ELLIS
FIRE WEATHER...ELLIS
000
FXUS66 KLOX 042047
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
145 PM PDT SAT SEP 4 2010
.SYNOPSIS...
SUNDAY WILL BEGIN A COOLING TREND TO THE AREA...ESPECIALLY
INLAND...AS A LOW PRESSURE SYSTEM GRADUALLY MOVES DOWN THE COAST
INTO CALIFORNIA BY MIDWEEK. BELOW NORMAL TEMPERATURES WILL CONTINUE
MONDAY THROUGH THE END OF THE WEEK...WITH AN INCREASE IN THE MARINE
LAYER.
&&
.SHORT TERM (TODAY-TUE)...TODAY WILL BE THE LAST OF THE BIG HEAT FOR
A WHILE AS HIGH PRESSURE OVER THE SOUTHWESTERN U.S. WEAKENS IN
RESPONSE TO A TROF MOVING INTO THE PAC NW. MOST INLAND AREAS SUNDAY
SHOULD SEE SEVERAL DEGREES OF COOLING AS ONSHORE FLOW STRENGTHENS.
INCREASING NORTHWEST FLOW AROUND PT CONCEPTION WILL BRING SOME WIND
THROUGH THE CANYONS OF THE SANTA YNEZ RANGE AND MAY BE ENOUGH TO
KEEP THE CLOUDS OUT OF SRN SBA COUNTY ALL TOGETHER. OTHERWISE, THE
MARINE LYR COVERAGE SUNDAY MORNING SHOULD BE PRETTY SIMILAR TO THIS
MORNING.
THE INCREASING NW WIND OFFSHORE SHOULD EVENTUALLY FORCE THE
DEVELOPMENT OF AN EDDY CIRCULATION OVER THE BIGHT REGION EITHER
SUNDAY NIGHT OR MONDAY MORNING. THIS WOULD TYPICALLY RESULT IN A
DEEPENING OF THE MARINE LYR AND MORE SIGNIFICANT COOLING MONDAY
AFTERNOON. AT THE SAME TIME THOUGH, WITH THE TROF MOVING INLAND SOME
NORTH TO NORTHEAST WINDS ALOFT ARE EXPECTED TO DEVELOP. THIS MAY
OFFSET AT LEAST SOME OF THE IMPACTS OF THE EDDY CIRCULATION AND
MARINE LYR COVERAGE MAY NOT BE AS WIDESPREAD AS PREVIOUSLY THOUGHT.
THE NAM RUNS THIS MORNING SHOWED 15-20 KT OF NORTHEAST WIND AT 850
MB THROUGH THE SANTA CLARA RIVER VALLEY SO WILL HAVE TO MONITOR THIS
TO SEE IF FUTURE RUNS CONTINUE THIS IDEA. FOR NOW, THOUGH, THE
FORECAST WAS LEFT PRETTY MUCH ALONE FOR MONDAY, INDICATING 5-10
DEGREES OF ADDITIONAL COOLING MOST AREAS WITH LOW CLOUDS REACHING
WELL INTO THE VALLEYS.
THE EDDY IS EXPECTED TO EXPAND TUESDAY WHILE AT THE SAME TIME THE
TROF ALONG THE WEST COAST DEEPENS. AS A RESULT, FURTHER COOLING OF
AFTERNOON TEMPERATURES IS EXPECTED WITH GREATER MARINE LYR COVERAGE.
.LONG TERM (WED-SAT)...TEMPS SHOULD BOTTOM OUT WED AS THE TROF AXIS
FINALLY SWINGS INLAND DURING THE AFTERNOON. A MUCH WEAKER IMPULSE
MOVING INTO THE PAC NW THU AND FRI WILL MAINTAIN THE TROF AND
CYCLONIC FLOW ALONG THE WEST COAST, SO SOME REBOUND OF TEMPS IS
EXPECTED BUT MINIMAL.
&&
.AVIATION...04/1800Z.
MID/UPPER LEVEL RIDGE OF HIGH PRESSURE OVER THE AREA WILL SHIFT
SOUTH. LIGHT UPPER LEVEL WEST WINDS WILL BECOME LIGHT WEST SOUTHWEST
AFTER 05/03Z WHILE LIGHT WEST AND NORTHWEST MID LEVEL WINDS PERSIST.
A WEAK PRESSURE GRADIENT WILL BECOME WEAK ONSHORE 04/20-05/03Z AND
AFTER 05/21Z. MARINE LAYER AROUND .5KFT WILL PERSIST WITH LITTLE
CHANGE.
KLAX...IT IS LIKELY INDEFINITE CIGS AND 1/2SM FG WILL RETURN
TONIGHT. THERE IS A CHANCE CURRENT SKY/VSBY CONDITIONS WILL PERSIST
THROUGH 05/07Z. AND IT IS LIKELY CLEAR SKIES AND 6SM HZ WILL RETURN
AFTER 05/19Z.
KBUR...VERY LIKELY CURRENT SKY/VSBY CONDITIONS WILL PERSIST.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...WOFFORD
AVIATION...30
SYNOPSIS...BARTLING
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KSGX 042032
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
200 PM PDT SAT SEP 4 2010
.SYNOPSIS...
HOT AND DRY AGAIN THIS AFTERNOON IN THE INLAND AREAS. COOLER NEAR
THE COAST WITH PATCHY LOW CLOUDS AND FOG LINGERING AT THE BEACHES.
COOLER NEXT WEEK WITH A DEEPER MARINE LAYER EXTENDING INLAND AND
BREEZY CONDITIONS IN THE MOUNTAINS AND DESERTS AT TIMES.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THIS AFTERNOON...PATCHY LOW CLOUDS AND FOG LINGERING AT THE BEACHES
WILL SPREAD INLAND TO THE COASTAL ZONES TONIGHT INTO SUNDAY MORNING.
THE MORNING SOUNDING FROM NKX SHOWS A STRONG SFC-BASED INVERSION
WITH DRY AIR AND NORTHERLY WINDS ABOVE.
THE HIGH PRESSURE RIDGE IS BEGINNING TO WEAKEN...BUT IT WILL BE HOT
AND DRY INLAND THIS AFTERNOON WITH TEMPERATURES 10 TO 15 DEGREES
ABOVE SEASONAL AVERAGES IN MANY LOCATIONS. TEMPS AT THE COAST WILL
REMAIN AT OR SLIGHTLY BELOW SEASONAL AVERAGES DUE TO THE MARINE
LAYER INFLUENCE. HUMIDITIES IN THE MTNS AND DESERTS WILL LOWER INTO
THE SINGLE DIGITS AGAIN THIS AFTERNOON.
THE MARINE LAYER WILL DEEPEN A LITTLE TONIGHT AND SUNDAY MORNING AS
THE UPPER LEVEL RIDGE CONTINUES TO WEAKEN IN RESPONSE TO A LOW
PRESSURE TROUGH MOVING INTO THE PAC NW. A COOLING TREND WILL BEGIN
SUNDAY WITH MAX TEMPS INLAND ABOUT 10 DEGREES LOWER THAN ON
SATURDAY. ONSHORE PRESSURE GRADIENTS WILL INCREASE AND PRODUCE GUSTY
WEST WINDS OVER THE MTNS AND DESERTS. PEAK WINDS OF 25-35 MPH CAN
OCCUR IN THE WINDIER LOCATIONS.
A SHORTWAVE WILL MOVE EWD THROUGH THE MEAN UPPER LEVEL TROUGH INTO
THE NRN ROCKIES ON MONDAY WITH LITTLE CHANGE IN
CONDITIONS...FOLLOWED BY A SECOND SHORTWAVE WHICH WILL DEEPEN THE
TROUGH OVER THE WEST COAST TUE THROUGH THU. THIS WILL BRING
CONSIDERABLE COOLING WITH TEMPERATURES WELL BELOW SEASONAL AVERAGES.
THE MARINE LAYER WILL DEEPEN TO THE EXTENT THAT LOW CLOUDS AND FOG
WILL EXTEND INLAND TO THE COASTAL SLOPES DURING THE NIGHTS AND
MORNINGS. AN INTERMITTENT COASTAL EDDY WILL DEVELOP. STRONGER
ONSHORE FLOW WILL CAUSE LOCAL BREEZY CONDITIONS IN THE MOUNTAINS AND
DESERTS AT TIMES.
SLIGHTLY WARMER FRIDAY AND SATURDAY AS THE TROUGH MOVES E...ALTHOUGH
SOCAL WILL LIKELY REMAIN UNDER CYCLONIC FLOW ALOFT.
&&
.AVIATION...
042000Z...STRATUS AND AREAS OF FOG...LOCALLY DENSE...LIKELY REMAIN
ALONG THE IMMEDIATE COAST THROUGH THE AFTERNOON AND MOVE INTO THE
COASTAL AIRPORTS AROUND 08Z. LIFR/VLIFR CIGS/VIS ARE EXPECTED AGAIN
TONIGHT IN THE COASTAL AREAS...CLEARING AROUND 16Z SUNDAY.
ABOVE THE MARINE LAYER...MOSTLY CLEAR SKIES AND UNRESTRICTED
VISIBILITIES THROUGH TONIGHT.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...PG
AVIATION...SS
000
FXUS66 KLOX 041814
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1112 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE WILL KEEP THE WEATHER HOT ACROSS INLAND AREAS
TODAY...WITH RELATIVELY COOL WEATHER NEAR THE COAST. AN UPPER LEVEL
TROUGH WILL MOVE INTO THE WEST COAST ON SUNDAY...AND COOLING WILL
BEGIN... ALTHOUGH IT WILL STILL BE VERY WARM INLAND. MORE
SIGNIFICANT COOLING IS LIKELY MONDAY THROUGH WEDNESDAY AS AN UPPER
LOW DROPS DOWN THE COAST...AND NIGHT THROUGH MORNING CLOUDS WILL
ADVANCE TO THE COASTAL SLOPES. BELOW NORMAL TEMPERATURE WILL
CONTINUE THROUGH FRIDAY.
&&
.SHORT TERM (TODAY-MON)...ALL SIGNS POINTING TOWARDS A WARMER DAY IN
ALL AREAS EXCEPT THE CENTRAL COAST. ACARS SOUNDINGS OUT OF LAX SHOW
AN EVEN LOWER MARINE INVERSION, WHICH IS SUPPORTED BY SURFACE
OBSERVATIONS FROM SURROUNDING HILLS WHERE TEMPS STAYED IN THE 70S
AND EVEN LOWER 80S ALL NIGHT. IN FACT, OBSERVATIONS FROM THE HIGHER
PORTIONS OF CATALINA ISLAND WERE ALREADY REPORTING TEMPS IN THE 90S
AT 8 AM AND CHEESEBORO RAWS IS ALREADY 97. E-W GRADIENTS DIDN`T GO
QUITE AS OFFSHORE AS THE NAM HAD SHOWN YESTERDAY BUT THEY DID TREND
OFFSHORE AND ACARS SOUNDING DO SHOW A LITTLE LOW LVL EASTERLY FLOW.
SO DESPITE THE RETURN OF DENSE FOG TO MUCH OF THE COAST THIS MORNING
WE SHOULD SEE EARLIER CLEARING IN MOST AREAS WITH SEVERAL DEGREES OF
WARMING ACROSS THE INTERIOR PORTION OF THE COASTAL PLAIN. STILL
COULD SEE SOME FOG AND LOW CLOUDS LINGERING AT A FEW BEACHES TODAY
BUT WITH THE WEAKER GRADIENTS TODAY I THINK MOST PLACES SHOULD GET
PLENTY OF SUN.
THE EXCEPTION TO THE WARMING TODAY WILL BE THE COASTAL PORTION OF
SLO AND NRN SBA COUNTIES WHERE THE VBG SOUNDING ACTUALLY SHOWED A
LITTLE COOLING BELOW 1500 FEET. THIS IS ALSO NICELY REFLECTED IN THE
SURROUNDING HILLS THERE WHERE TEMPS THIS MORNING ARE DOWN AS MUCH AS
15 DEGREES.
***FROM PREVIOUS DISCUSSION***
THE UPPER HIGH WILL BEGIN TO WEAKEN AND SHIFT EWD TONIGHT AND SUNDAY
AS A TROUGH MOVES INTO THE PAC NW. LOW CLOUDS MAY PUSH A BIT FARTHER
INLAND ACROSS THE CSTL PLAIN TONIGHT/SUN MORNING ACROSS L.A. AND VTU
COUNTIES...WITH WDSPRD CLOUDS EXPECTED ON THE CENTRAL CST.
HOWEVER...N-S GRADS ACROSS SBA COUNTY COULD HOLD STRATUS AT BAY...OR
AT LEAST DELAY THE ONSET OF ANY CLOUDS UNTIL NEAR DAYBREAK ON
SUNDAY. N-S GRADS WILL LIKELY BE STRONG ENOUGH TO PRODUCE SOME
LOCALLY GUSTY WINDS THRU AND BELOW PASSES AND CANYONS OF THE SANTA
YNEZ RANGE...BUT WINDS SHOULD STAY BELOW ADVISORY LEVELS. THE MARINE
LAYER SHOULD REMAIN SHALLOW ENOUGH SO THAT THERE MAY BE SOME DENSE
FOG ON THE CSTL PLAIN...AND IT APPEARS THAT CLOUDS WILL STAY OUT OF
THE VLYS. LOWERING HEIGHTS/THICKNESSES AND STRONGER ONSHORE GRADS
WILL LIKELY LEAD TO SEVERAL DEGREES OF COOLING ACROSS MUCH OF THE
REGION ON SUN...WITH COOLING ON THE ORDER OF 6 TO 12 DEGREES LIKELY
IN THE VLYS AND ACROSS INTERIOR SECTIONS OF THE CSTL PLAIN.
STILL...TEMPS SHOULD BE NEAR OR A BIT ABOVE NORMAL IN INLAND AREAS.
N-S WILL PRODUCE ANOTHER ROUND OF GUSTY WINDS THRU AND BELOW PASSES
AND CANYONS OF SRN SBA COUNTY AND POSSIBLY THRU THE I-5 CORRIDOR
SUNDAY NIGHT...AND THE WRF SHOWS A WELL DEVELOPED EDDY CIRCULATION
DEVELOPING. THIS SHOULD HELP DEEPEN THE MARINE LAYER S OF PT
CONCEPTION...AND EXPECT WDSPRD CLOUDS IN CSTL SXNS OF L.A. AND VTU
COUNTIES...LIKELY SPREADING INTO MANY VALLEY AREAS LATE SUN
NIGHT/MON MORNING. WITH THE NLY GRADS...IT MAY BE TOUGH FOR CLOUDS
TO REACH SRN SBA COUNTY UNTIL DAYBREAK ON MONDAY. AND...PRESUMABLY
BECAUSE OF THE GRADS...THE WRF SHOWS LESS IN THE WAY OF CLOUDS ON
THE CENTRAL COAST AS WELL. EXPECT ANOTHER 6 TO 10 DEGREES OF COOLING
IN MOST AREAS ON MONDAY...WITH THE BEST COOLING IN THE VLYS.
.LONG TERM (TUE-FRI)...AN UPPER LOW WILL DROP SWD DOWN THE WEST
COAST TUE THRU WED...WITH A BROAD TROUGH ACROSS THE REGION GRADUALLY
SHARPENING UP. LOWERING HEIGHTS AND THICKNESSES...AND COOLING AT 850
AND 950 MB...ALONG WITH INCREASING ONSHORE FLOW AND A DEEPENING
MARINE LAYER WILL LIKELY CONTINUE TO PRODUCE SOME COOLING EACH DAY.
ALTHOUGH THE UPPER LOW WILL MOVE INTO THE NRN ROCKIES ON
THU...STRONGLY CYCLONIC FLOW ALOFT WILL LINGER ACROSS THE REGION.
EXPECT THE MARINE LAYER TO DEEPEN ENOUGH TO PUSH CLOUDS TO THE
CSTL SLOPES FOR TUE NIGHT AND WED NIGHT...AND THERE WILL PROBABLY BE
SOME DRIZZLE THOSE NIGHTS AS WELL. TEMPS WILL BE WELL BELOW NORMAL
ACROSS THE REGION TUE THRU THU. SOME WARMING MAY BEGIN ON FRI AS THE
TROUGH MOVES EWD AND HEIGHTS BEGIN TO REBOUND.
&&
.AVIATION...04/1800Z.
MID/UPPER LEVEL RIDGE OF HIGH PRESSURE OVER THE AREA WILL SHIFT
SOUTH. LIGHT UPPER LEVEL WEST WINDS WILL BECOME LIGHT WEST SOUTHWEST
AFTER 05/03Z WHILE LIGHT WEST AND NORTHWEST MID LEVEL WINDS PERSIST.
A WEAK PRESSURE GRADIENT WILL BECOME WEAK ONSHORE 04/20-05/03Z AND
AFTER 05/21Z. MARINE LAYER AROUND .5KFT WILL PERSIST WITH LITTLE
CHANGE.
KLAX...IT IS LIKELY INDEFINITE CIGS AND 1/2SM FG WILL RETURN
TONIGHT. THERE IS A CHANCE CURRENT SKY/VSBY CONDITIONS WILL PERSIST
THROUGH 05/07Z. AND IT IS LIKELY CLEAR SKIES AND 6SM HZ WILL RETURN
AFTER 05/19Z.
KBUR...VERY LIKELY CURRENT SKY/VSBY CONDITIONS WILL PERSIST.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...WOFFORD/BRUNO
SYNOPSIS...DB
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KMTR 041735
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1035 AM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 9:15 AM PDT SATURDAY...SATL IMAGERY IS SHOWING
STRATUS COVERING THE COAST AND INTO THE BAYS AND COASTAL VALLEYS. IN
FACT...STRATUS IS DOWN THE SALINAS VALLEY TO NEAR PASO ROBLES. THE
EAST BAY VALLEYS ARE CLEAR THIS MORNING.
THE MARINE INVERSION HAS SLOWLY DEEPENED THIS MORNING. THE FT ORD
PROFILER IS INDC THAT THE MARINE INVERSION IS NEAR 1200 FEET WITH THE
BAY AREA SODARS INDC A 1400 FT MARINE INVERSION. TEMPS THIS MORNING
ARE RUNNING WELL BELOW YESTERDAY MORNING...AS MUCH AS 17 DEGREES AT
SAN RAFAEL. THE GRADIENT PICTURE IS INDC A 2.9 MB NORTHERLY GRADIENT
BETWEEN ARCATA-SFO AND AN ONSHORE GRADIENT OF 2.4 MB BETWEEN SFO-SAC.
A TROUGH IS MOVING INTO THE PACIFIC NORTHWEST AT THIS TIME. AS IT
MOVES EAST A SURFACE HIGH WILL BUILD INTO THE NORTHERN GREAT BASIN.
THIS WILL RESULT IN A NORTHERLY FLOW IN THE NORTH BAY STARTING
TONIGHT...WHICH COULD RESULT IN CLEAR SKIES NORTH OF THE GOLDEN GATE.
THE NORTH BAY COULD ALSO WARM UP A BIT ON SUNDAY AS WELL. AS THE SFC
HIGH CONTINUES TO BUILD INTO THE GREAT BASIN THE OFFSHORE FLOW WILL
SPREAD SOUTH ACROSS THE ENTIRE DISTRICT ON MONDAY. MONDAY COULD BE A
WARM DAY...EVEN ON THE COAST WITH THE OFFSHORE FLOW. LOOKS LIKE LABOR
DAY WILL BE A WARM SUNNY DAY ACROSS THE DISTRICT.
NO UPDATES NEEDED AT THIS TIME.
&&
.AVIATION...AS OF 10:35 AM PDT SATURDAY...SKIES WERE RAPIDLY
CLEARING INLAND ON SATURDAY MORNING...AND EXPECT VFR CONDITIONS AT
ALL TERMINALS BY 19Z. THE MARINE LAYER WILL REMAIN ABOUT 1500 FEET
DEEP THROUGH SUNDAY MORNING. HOWEVER...NORTHERLY SURFACE GRADIENTS
WILL INCREASE...WHICH WILL DELAY INLAND DEVELOPMENT OF LOW CIGS IN
THE SF BAY AREA UNTIL LATE TONIGHT...WELL PAST THE EVENING RUSH. IFR
CIGS WILL DEVELOP NEAR MONTEREY BAY BY 02-03Z THIS EVENING.
INCREASING NORTHERLY FLOW ON SUNDAY WILL RESULT IN EARLIER CLEARING
WITH VFR CONDITIONS EXPECTED IN MOST AREAS BY 17Z SUNDAY MORNING.
MODERATE WEST WINDS ARE FORECAST FROM MID AFTERNOON THROUGH EARLY
EVENING.
&&
.VICINITY OF KSFO...VFR CONDITIONS THROUGH THE EVENING. WEST TO
NORTHWEST WINDS INCREASING TO 17G23KT BY 23Z AND CONTINUING THROUGH
04Z. IFR CIGS WILL LIKELY DEVELOP LATE TONIGHT AROUND 12Z...BUT THEN
CLEAR BY 17Z ON SUNDAY MORNING.
.KSFO BRIDGE APPROACH...VFR CONDITIONS DEVELOPING BY 18Z AND
CONTINUING THROUGH THE EVENING WITH IFR CIGS NOT LIKELY UNTIL 12Z
LATE TONIGHT. CLEARING EXPECTED BY 17Z SUNDAY MORNING.
.MRY BAY AREA TERMINALS...IFR CIGS THRU 19Z. VFR CONDITIONS EXPECTED
FROM MIDDAY THROUGH THE AFTERNOON. IFR CIGS WILL LIKELY REDEVELOP
BETWEEN 01-03Z EARLY THIS EVENING. CLEARING EXPECTED EARLIER ON
SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.AFTERNOON...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: DYKEMA
000
FXUS65 KPSR 041653
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST SAT SEP 4 2010
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL BRING A CONTINUATION OF WELL ABOVE
NORMAL DAYTIME HIGH TEMPERATURES THROUGH SUNDAY. EXPECT TEMPERATURES
TO DRIFT LOWER NEXT WEEK AS THE HIGH PRESSURE SYSTEM MOVES OFF TO
THE EAST...WHILE A COUPLE OF RATHER STRONG LOW PRESSURE SYSTEMS MOVE
THROUGH THE INTERMOUNTAIN WEST. IN FACT...SLIGHTLY BELOW NORMAL
TEMPERATURES WILL PREVAIL ACROSS THE REGION WEDNESDAY THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF ISOLATED THUNDERSTORMS
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX TODAY THROUGH
NEXT TUESDAY.
&&
.DISCUSSION...
AZ SOUNDINGS THIS MORNING SHOW A NOTABLE GAINS IN MOISTURE FROM
YESTERDAY MORNING...AT LEAST PART OF WHICH WAS REALIZED DURING THE
DAY YESTERDAY. ACCORDINGLY...THE TEMPERATURE PROFILES IN THE LOWER
LEVELS ARE NOT AS WARM. THUS TEMPS OVER SOUTH-CENTRAL ARIZONA WILL
NOT BE QUITE AS HOT...AS IS FORECAST. ALOFT HOWEVER THERE HAS BEEN
WARMING ABOVE 500 MB AND THIS WILL SERVE TO REDUCE INSTABILITY
DESPITE THE MOISTURE GAIN...THOUGH AN ISOLATED THUNDERSTORM IS STILL
POSSIBLE OVER ZONE 24 AND MORE LIKELY OVER THE WHITE MOUNTAINS AND
PORTIONS OF SOUTHEAST ARIZONA. WITH NO SOUNDING AVAILABLE FROM THE
YUMA AREA ON WEEKENDS...THE TRENDS IN THE MOISTURE PROFILE DO NOT
NECESSARILY APPLY TO FAR WESTERN ARIZONA AND SOUTHEAST CALIFORNIA.
GPS IPW SENSORS SUGGEST THAT THEY DONT BECAUSE PRECIPITABLE WATER
VALUES ARE LOWER DESPITE THE GULF SURGE EVIDENT AT YUMA. RADAR WIND
PROFILE SHOWS THIS AS BEING SHALLOW...AND WEAKENING...AS WOULD BE
EXPECTED FROM AN MCS OUTLFOW TYPE OF SURGE. RUC FORECAST SOUNDING
REFLECTS THIS SURGE AND SHOWS IT BEING QUITE SHALLOW...MAYBE TOO
SHALLOW. NET EFFECT WILL BE SOME SLIGHT COOLING...MAINLY IN THE
SOUTHERN PORTIONS OF THE LOWER COLORADO RIVER VALLEY...BUT NOT
ENOUGH TO CANCEL THE EXCESSIVE HEAT WARNING.
12Z MODELS CONTINUE TO SHOW THE ANTICYCLONE CENTERED OVER SOUTHERN
CALIFORNIA WEAKENING AND SHIFTING EASTWARD SUNDAY AS A TROUGH OVER
WESTERN CANADA AND THE PACIFIC NORTHWEST MOVES INLAND AND DEEPENS.
MORE LATER.
PREVIOUS DISCUSSION...
UPPER LEVEL HIGH PRESSURE THAT BROUGHT EXCESSIVE HEAT TO THE LOWER
DESERT ON FRIDAY WAS CENTERED JUST NORTHWEST OF LOS ANGELES THIS
MORNING...WITH RIDGE AXIS EXTENDING EAST ACROSS CENTRAL ARIZONA.
CENTER OF THE HIGH WILL MIGRATE SLOWLY EAST TODAY AND TONIGHT...THEN
WEAKEN SLOWLY AND MOVES TO SOUTHERN NEW MEXICO BY SUNDAY EVENING. AS
SUCH...WELL ABOVE NORMAL DAYTIME HIGHS WILL PERSIST THROUGH SUNDAY.
FORECAST SOUNDINGS INDICATE BOUNDARY LAYER TEMP WILL BE...ON
AVERAGE...1-3 F LOWER OVER THE LOWER DESERT TODAY COMPARED TO
FRIDAY...AND 1-2 F LOWER SUNDAY COMPARED TO TODAY. EXCESSIVE HEAT
WARNING...DRIVEN BY EXPECTED MAX TEMPS...WILL REMAIN IN EFFECT OVER
FAR SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA TODAY. AS EXPECTED...
ATMOSPHERE DID MOISTEN UP ACROSS SOUTH-CENTRAL AZ COMMENCING FRIDAY
AFTERNOON...AND SOME MOIST ADVECTION WILL OCCUR ACROSS WESTERN AZ
AND EXTREME SOUTHEAST CALIFORNIA TODAY. STILL...SFC DEW POINTS WILL
BE BELOW CLIMO...AND THAT...COMBINED WITH EXPECTED MID-LEVEL
WARMING...RESULTS IN DESERT SOUNDINGS PRETTY MUCH DEVOID OF CAPE.
CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGHER TERRAIN EAST OF
PHOENIX TODAY THROUGH LABOR DAY...BUT THATS ABOUT IT. RATHER STRONG
TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE INTERMOUNTAIN WEST...
MAINLY TO OUR NORTH...LATE SUNDAY INTO LABOR DAY...WHILE UPPER HIGH
MOVES WELL OFF TO OUR SOUTHEAST. AS RIDGE LOSES ITS GRIP ON THE
SOUTHWEST UNITED STATES...A COOLING TREND WILL COMMENCE...WITH LABOR
DAY HIGH TEMPS 4-6 DEGREES LOWER THAN WHAT OCCURS SUNDAY (EVEN
SO...MAX TEMPS LABOR DAY WILL BE A FEW DEGREES ABOVE CLIMO).
IN EXTENDED...ECMWF AND GFS AGREE THAT SOUTHWESTERLY FLOW WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A RATHER STRONG
TROUGH OF LOW PRESSURE FORECAST TO DEVELOP ALONG OR NEAR THE PACIFIC
COAST...THEN MOVE SLOWLY EAST ACROSS THE INTERMOUNTAIN WEST LATER IN
THE WEEK. FORECAST TEMPS SHOULD BE NEAR NORMAL TUESDAY...BUT LOWER
TO SLIGHTLY BELOW NORMAL THE REST OF THE WORK WEEK. IN ADVANCE OF
THE STRONG TROUGH...A WEAK WEATHER DISTURBANCE IS FORECAST TO BE
EJECTED EAST ACROSS SOUTHERN AZ/SONORA MEXICO ON TUESDAY...AND THIS
SYSTEM MAY TAP INTO ENOUGH MOISTURE TO INCREASE THE CHANCE FOR A
THUNDERSTORM MAINLY OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
WINDS WILL GENERALLY REMAIN OUT OF THE SOUTHEAST THROUGH THE DAY AND
INTO SUNDAY MORNING. BRIEF PERIOD OF WEST/NORTHWEST WINDS ARE
POSSIBLE DURING THE EVENING.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKY AND LIGHT WINDS THROUGH SATURDAY EVENING.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
BROAD TROUGHING WILL DOMINATE THE WEATHER PATTERN DURING THE
EXTENDED FORECAST PERIOD. TEMPERATURES WILL BE COOLING AS A RESULT.
SOME AFTERNOONS WILL BE BREEZY WITH WINDS GUSTING INTO THE 20 TO 30
MPH RANGE. VERY DRY AIR WILL ALSO SPREAD ACROSS MOST OF THE
SOUTHWEST PUSHING AFTERNOON HUMIDITY VALUES QUITE LOW THOUGH THERE
WILL BE DECENT OVERNIGHT RECOVERY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...AJ/DG
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
000
FXUS66 KSGX 041628
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HOT AND DRY AGAIN TODAY IN THE INLAND AREAS. NEAR THE COAST IT WILL
BE COOLER WITH PATCHY LOW CLOUDS AND FOG LINGERING AT THE BEACHES
INTO THE AFTERNOON. COOLER NEXT WEEK WITH A DEEPER MARINE LAYER
EXTENDING INLAND AND BREEZY CONDITIONS IN THE MOUNTAINS AND DESERTS
AT TIMES.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THIS MORNING...PATCHY LOW CLOUDS AND FOG IN THE COSATAL AREAS COULD
LINGER AT THE BEACHES INTO THIS AFTERNOON. THE MORNING SOUNDING FROM
NKX SHOWS A STRONG SFC-BASED INVERSION WITH DRY AIR AND NORTHERLY
WINDS ABOVE.
THE HIGH PRESSURE RIDGE WILL REMAIN IN PLACE TODAY AND BRING ANOTHER
HOT DAY INLAND WITH TEMPERATURES 10 TO 15 DEGREES ABOVE SEASONAL
AVERAGES IN MANY LOCATIONS. TEMPS AT THE COAST WILL REMAIN AT OR
SLIGHTLY BELOW SEASONAL AVERAGES DUE TO THE MARINE LAYER INFLUENCE.
HUMIDITIES IN THE MTNS AND DESERTS WILL LOWER INTO THE SINGLE DIGITS
AGAIN TODAY.
THE MARINE LAYER WILL DEEPEN A LITTLE TONIGHT AND SUNDAY MORNING AS
THE UPPER LEVEL RIDGE BEGINS TO WEAKEN IN RESPONSE TO A LOW PRESSURE
TROUGH MOVING INTO THE PAC NW. A COOLING TREND WILL BEGIN SUNDAY
WITH MAX TEMPS INLAND ABOUT 10 DEGREES LOWER THAN ON SATURDAY.
ONSHORE PRESSURE GRADIENTS WILL INCREASE AND PRODUCE GUSTY WEST
WINDS OVER THE MTNS AND DESERTS. PEAK WINDS OF 25-35 MPH CAN OCCUR
IN THE WINDIER LOCATIONS.
A SHORTWAVE WILL MOVE EWD THROUGH THE MEAN UPPER LEVEL TROUGH INTO
THE NRN ROCKIES ON MONDAY WITH LITTLE CHANGE IN
CONDITIONS...FOLLOWED BY A SECOND SHORTWAVE WHICH WILL DEEPEN THE
TROUGH OVER THE WEST COAST TUE THROUGH THU. THIS WILL BRING
CONSIDERABLE COOLING WITH TEMPERATURES WELL BELOW SEASONAL AVERAGES.
THE MARINE LAYER WILL DEEPEN TO THE EXTENT THAT LOW CLOUDS AND FOG
WILL EXTEND INLAND TO THE COASTAL SLOPES DURING THE NIGHTS AND
MORNINGS. AN INTERMITTENT COASTAL EDDY WILL DEVELOP. STRONGER
ONSHORE FLOW WILL CAUSE LOCAL BREEZY CONDITIONS IN THE MOUNTAINS AND
DESERTS AT TIMES.
SLIGHTLY WARMER FRIDAY AND SATURDAY AS THE TROUGH MOVES E...ALTHOUGH
SOCAL WILL LIKELY REMAIN UNDER CYCLONIC FLOW ALOFT.
&&
.AVIATION...
041445Z...AREAS OF FOG...LOCALLY DENSE...ALONG THE COAST WITH CIGS
BETWEEN 100-400 FT MSL WILL CONTINUE THROUGH 16-17Z. STRATUS/FOG
WILL LIKELY REMAIN ALONG THE IMMEDIATE COAST THROUGH THE DAY AND
MOVE INTO THE COASTAL AIRPORTS AROUND 08Z. LIFR/VLIFR CIGS/VIS ARE
EXPECTED AGAIN TONIGHT IN THE COASTAL AREAS...CLEARING AROUND 16Z
SUNDAY.
ABOVE THE MARINE LAYER...MOSTLY CLEAR SKIES AND UNRESTRICTED
VISIBILITIES THROUGH TONIGHT. A FEW CU MAY DEVELOP OVER THE
MOUNTAINS IN THE AFTERNOON.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...PG
AVIATION...SS
000
FXUS66 KMTR 041625
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
925 AM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 9:15 AM PDT SATURDAY...SATL IMAGERY IS SHOWING
STRATUS COVERING THE COAST AND INTO THE BAYS AND COASTAL VALLEYS. IN
FACT...STRATUS IS DOWN THE SALINAS VALLEY TO NEAR PASO ROBLES. THE
EAST BAY VALLEYS ARE CLEAR THIS MORNING.
THE MARINE INVERSION HAS SLOWLY DEEPENED THIS MORNING. THE FT ORD
PROFILER IS INDC THAT THE MARINE INVERSION IS NEAR 1200 FEET WITH THE
BAY AREA SODARS INDC A 1400 FT MARINE INVERSION. TEMPS THIS MORNING
ARE RUNNING WELL BELOW YESTERDAY MORNING...AS MUCH AS 17 DEGREES AT
SAN RAFAEL. THE GRADIENT PICTURE IS INDC A 2.9 MB NORTHERLY GRADIENT
BETWEEN ARCATA-SFO AND AN ONSHORE GRADIENT OF 2.4 MB BETWEEN SFO-SAC.
A TROUGH IS MOVING INTO THE PACIFIC NORTHWEST AT THIS TIME. AS IT
MOVES EAST A SURFACE HIGH WILL BUILD INTO THE NORTHERN GREAT BASIN.
THIS WILL RESULT IN A NORTHERLY FLOW IN THE NORTH BAY STARTING
TONIGHT...WHICH COULD RESULT IN CLEAR SKIES NORTH OF THE GOLDEN GATE.
THE NORTH BAY COULD ALSO WARM UP A BIT ON SUNDAY AS WELL. AS THE SFC
HIGH CONTINUES TO BUILD INTO THE GREAT BASIN THE OFFSHORE FLOW WILL
SPREAD SOUTH ACROSS THE ENTIRE DISTRICT ON MONDAY. MONDAY COULD BE A
WARM DAY...EVEN ON THE COAST WITH THE OFFSHORE FLOW. LOOKS LIKE LABOR
DAY WILL BE A WARM SUNNY DAY ACROSS THE DISTRICT.
NO UPDATES NEEDED AT THIS TIME.
&&
.AVIATION...AS OF 4:22 AM PDT SATURDAY...SATELLITE IMAGERY AND
SURFACE OBSERVATIONS INDICATE LOW CLOUDS OVER ALL TERMINAL SITES AT
THIS TIME WITH CEILINGS RANGING FROM A FEW HUNDRED FEET TO 1000
FEET. THE MARINE LAYER DEPTH HAS RAMPED UP TO ABOUT 1400 FEET PER
THE FORT ORD PROFILER...AND THE ONSHORE SURFACE PRESSURE GRADIENT
HAS INCREASED TO NEARLY 3 MB FROM SFO TO SAC. EXPECT CEILINGS TO
BREAK UP BY 18Z MOST AREAS.
&&
.VICINITY OF KSFO...IFR CIGS THRU 18Z. GUSTY NORTHWEST WINDS WILL
ONCE AGAIN DEVELOP AROUND 21Z WITH GUSTS TO 22 KNOTS.
.KSFO BRIDGE APPROACH...IFR CIGS OVER THE APPROACH. VFR RETURNING BY
18Z.
.MRY BAY AREA TERMINALS...LIFR CIGS THRU 17Z AND LOCAL IFR
VISIBILITIES THRU 14Z. LOW CLOUDS AND FOG CLEARING TO THE COAST
BETWEEN 18Z AND 19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.AFTERNOON...SCA...ALL COASTAL WATERS EXCEPT PIGEON PT
TO PT PINOS 0-10 NM.
SCA...SFO BAY.
&&
$$
PUBLIC FORECAST: MHS
AVIATION/MARINE: SSA/DYKEMA
000
FXUS66 KHNX 041620
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
920 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL CONTINUE TO BUILD OVER CENTRAL CALIFORNIA.
STRONG WARMING WILL SEND TEMPERATURES SOME 10 TO 15 DEGREES ABOVE
AVERAGE THROUGH AT LEAST SATURDAY. AN UPPER-LEVEL TROUGH WILL BRING
COOLER TEMPERATURES FOR LABOR DAY AND THE FIRST PART OF NEXT WEEK.
&&
.DISCUSSION...
CLEAR AND DRY CONDITIONS THIS MORNING. SOME SMOKE FROM THE
SHEEP WILDFIRE FLOWING ALONG THE KINGS RIVER IN THE SIERRA INTO
THE SAN JOAQUIN VALLEY. THE AIR QUALITY ALERT IS BEING EXTENDED
ANOTHER 24 HOURS AS THE UPPER HIGH OVER THE REGION CONTINUES TO
PROVIDE A STALE AIR MASS WITH LITTLE MIXING. TEMPERATURE TRENDS
ARE A BIT COOLER AT MOST LOCALES EXCEPT TOWARDS THE MOJAVE DESERT.
PROFILERS SHOW LOW LEVEL TEMPERATURE CHANGE OF 2C DEGREES AT
CHOWCHILLA WITH LITTLE CHANGE AT GORMAN. NO UPDATES EXPECTED TO
GOING FORECAST. BEST COOLING TOWARDS THE MERCED AREA AND HIGHER
ELEVATIONS OF THE SIERRA. OTHERWISE LITTLE CHANGE TOWARDS KERN
MOUNTAINS AND DESERT.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL UNDER GENERALLY CLEAR SKIES ACROSS THE
CENTRAL CALIFORNIA INTERIOR THROUGH 18Z SUNDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BROTHERTON
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KLOX 041557
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
900 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE WILL KEEP THE WEATHER HOT ACROSS INLAND AREAS
TODAY...WITH RELATIVELY COOL WEATHER NEAR THE COAST. AN UPPER LEVEL
TROUGH WILL MOVE INTO THE WEST COAST ON SUNDAY...AND COOLING WILL
BEGIN... ALTHOUGH IT WILL STILL BE VERY WARM INLAND. MORE
SIGNIFICANT COOLING IS LIKELY MONDAY THROUGH WEDNESDAY AS AN UPPER
LOW DROPS DOWN THE COAST...AND NIGHT THROUGH MORNING CLOUDS WILL
ADVANCE TO THE COASTAL SLOPES. BELOW NORMAL TEMPERATURE WILL
CONTINUE THROUGH FRIDAY.
&&
.SHORT TERM (TODAY-MON)...ALL SIGNS POINTING TOWARDS A WARMER DAY IN
ALL AREAS EXCEPT THE CENTRAL COAST. ACARS SOUNDINGS OUT OF LAX SHOW
AN EVEN LOWER MARINE INVERSION, WHICH IS SUPPORTED BY SURFACE
OBSERVATIONS FROM SURROUNDING HILLS WHERE TEMPS STAYED IN THE 70S
AND EVEN LOWER 80S ALL NIGHT. IN FACT, OBSERVATIONS FROM THE HIGHER
PORTIONS OF CATALINA ISLAND WERE ALREADY REPORTING TEMPS IN THE 90S
AT 8 AM AND CHEESEBORO RAWS IS ALREADY 97. E-W GRADIENTS DIDN`T GO
QUITE AS OFFSHORE AS THE NAM HAD SHOWN YESTERDAY BUT THEY DID TREND
OFFSHORE AND ACARS SOUNDING DO SHOW A LITTLE LOW LVL EASTERLY FLOW.
SO DESPITE THE RETURN OF DENSE FOG TO MUCH OF THE COAST THIS MORNING
WE SHOULD SEE EARLIER CLEARING IN MOST AREAS WITH SEVERAL DEGREES OF
WARMING ACROSS THE INTERIOR PORTION OF THE COASTAL PLAIN. STILL
COULD SEE SOME FOG AND LOW CLOUDS LINGERING AT A FEW BEACHES TODAY
BUT WITH THE WEAKER GRADIENTS TODAY I THINK MOST PLACES SHOULD GET
PLENTY OF SUN.
THE EXCEPTION TO THE WARMING TODAY WILL BE THE COASTAL PORTION OF
SLO AND NRN SBA COUNTIES WHERE THE VBG SOUNDING ACTUALLY SHOWED A
LITTLE COOLING BELOW 1500 FEET. THIS IS ALSO NICELY REFLECTED IN THE
SURROUNDING HILLS THERE WHERE TEMPS THIS MORNING ARE DOWN AS MUCH AS
15 DEGREES.
***FROM PREVIOUS DISCUSSION***
THE UPPER HIGH WILL BEGIN TO WEAKEN AND SHIFT EWD TONIGHT AND SUNDAY
AS A TROUGH MOVES INTO THE PAC NW. LOW CLOUDS MAY PUSH A BIT FARTHER
INLAND ACROSS THE CSTL PLAIN TONIGHT/SUN MORNING ACROSS L.A. AND VTU
COUNTIES...WITH WDSPRD CLOUDS EXPECTED ON THE CENTRAL CST.
HOWEVER...N-S GRADS ACROSS SBA COUNTY COULD HOLD STRATUS AT BAY...OR
AT LEAST DELAY THE ONSET OF ANY CLOUDS UNTIL NEAR DAYBREAK ON
SUNDAY. N-S GRADS WILL LIKELY BE STRONG ENOUGH TO PRODUCE SOME
LOCALLY GUSTY WINDS THRU AND BELOW PASSES AND CANYONS OF THE SANTA
YNEZ RANGE...BUT WINDS SHOULD STAY BELOW ADVISORY LEVELS. THE MARINE
LAYER SHOULD REMAIN SHALLOW ENOUGH SO THAT THERE MAY BE SOME DENSE
FOG ON THE CSTL PLAIN...AND IT APPEARS THAT CLOUDS WILL STAY OUT OF
THE VLYS. LOWERING HEIGHTS/THICKNESSES AND STRONGER ONSHORE GRADS
WILL LIKELY LEAD TO SEVERAL DEGREES OF COOLING ACROSS MUCH OF THE
REGION ON SUN...WITH COOLING ON THE ORDER OF 6 TO 12 DEGREES LIKELY
IN THE VLYS AND ACROSS INTERIOR SECTIONS OF THE CSTL PLAIN.
STILL...TEMPS SHOULD BE NEAR OR A BIT ABOVE NORMAL IN INLAND AREAS.
N-S WILL PRODUCE ANOTHER ROUND OF GUSTY WINDS THRU AND BELOW PASSES
AND CANYONS OF SRN SBA COUNTY AND POSSIBLY THRU THE I-5 CORRIDOR
SUNDAY NIGHT...AND THE WRF SHOWS A WELL DEVELOPED EDDY CIRCULATION
DEVELOPING. THIS SHOULD HELP DEEPEN THE MARINE LAYER S OF PT
CONCEPTION...AND EXPECT WDSPRD CLOUDS IN CSTL SXNS OF L.A. AND VTU
COUNTIES...LIKELY SPREADING INTO MANY VALLEY AREAS LATE SUN
NIGHT/MON MORNING. WITH THE NLY GRADS...IT MAY BE TOUGH FOR CLOUDS
TO REACH SRN SBA COUNTY UNTIL DAYBREAK ON MONDAY. AND...PRESUMABLY
BECAUSE OF THE GRADS...THE WRF SHOWS LESS IN THE WAY OF CLOUDS ON
THE CENTRAL COAST AS WELL. EXPECT ANOTHER 6 TO 10 DEGREES OF COOLING
IN MOST AREAS ON MONDAY...WITH THE BEST COOLING IN THE VLYS.
.LONG TERM (TUE-FRI)...AN UPPER LOW WILL DROP SWD DOWN THE WEST
COAST TUE THRU WED...WITH A BROAD TROUGH ACROSS THE REGION GRADUALLY
SHARPENING UP. LOWERING HEIGHTS AND THICKNESSES...AND COOLING AT 850
AND 950 MB...ALONG WITH INCREASING ONSHORE FLOW AND A DEEPENING
MARINE LAYER WILL LIKELY CONTINUE TO PRODUCE SOME COOLING EACH DAY.
ALTHOUGH THE UPPER LOW WILL MOVE INTO THE NRN ROCKIES ON
THU...STRONGLY CYCLONIC FLOW ALOFT WILL LINGER ACROSS THE REGION.
EXPECT THE MARINE LAYER TO DEEPEN ENOUGH TO PUSH CLOUDS TO THE
CSTL SLOPES FOR TUE NIGHT AND WED NIGHT...AND THERE WILL PROBABLY BE
SOME DRIZZLE THOSE NIGHTS AS WELL. TEMPS WILL BE WELL BELOW NORMAL
ACROSS THE REGION TUE THRU THU. SOME WARMING MAY BEGIN ON FRI AS THE
TROUGH MOVES EWD AND HEIGHTS BEGIN TO REBOUND.
&&
.AVIATION...04/1200Z.
VERY LOW CONFIDENCE IN THE 12Z COASTAL TAFS IN CONTRAST TO HIGH
CONFIDENCE IN THE VALLEY TAFS. A SHALLOW MARINE LAYER OF AROUND 700
FEET WITH LIFR CONDITIONS IS STRUGGLING TO MAINTAIN A PRESENCE IN
THE VICINITY OF THE IMMEDIATE COAST AMIDST AN INCREASING ONSLAUGHT
OF OFFSHORE TRENDS IN THE PRESSURE GRADIENTS. THE RESULT SEEMS TO BE
CAUSING THE LOW CLOUDS AND DENSE FOG TO OSCILLATE BACK AND FORTH AT
THE COAST AND THE COASTAL TAF SITES ARE SHOWING LITTLE IN THE WAY OF
TEMPORAL CONSISTENCY. THE VALLEY TAFS WILL REMAIN VFR THROUGH THE
DAY.
KLAX...VERY LOW CONFIDENCE IN THE 12Z TAF WITH INTERMITTENT LIFR
CONDITIONS INTERSPERSED WITH OCCASIONAL VFR CONDITIONS. ALMOST NO
TEMPORAL CONSISTENCY.
KBUR...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE DAY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...WOFFORD/BRUNO
AVIATION...SWEET
SYNOPSIS...DB
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KSTO 041553
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
900 AM PDT SAT SEP 4 2010
.DISCUSSION...
MODERATE DELTA BREEZE THIS MORNING IS HELPING TO COOL THE INTERIOR
OFF. TEMPERATURES SHOULD REMAIN COMFORTABLE THIS MORNING BEFORE
WARMING UP INTO THE LOW TO MID 90S AROUND SACRAMENTO TO UPPER 90S
NEAR MODESTO AND REDDING. A WEAK LOW PRESSURE AREA WILL MOVE THROUGH
THE REGION TONIGHT. THE LOW WILL HELP TO COOL TEMPERATURES A LITTLE
IN THE VALLEY BUT MORE NOTICEABLE IN THE MOUNTAINS. SUNDAY WILL
GENERALLY BE THE COOLEST DAY THIS WEEKEND FOR ALMOST ALL AREAS
EXCEPT PERHAPS THE DELTA WHICH MAY HAVE ITS COOLEST DAY TODAY.
NORTHERLY WINDS WILL ALSO DEVELOP ON SUNDAY AND WILL LIMIT THE COOL
DOWN. CONDITIONS LOOK LIKE THEY MAY BE BREEZY OVER THE NORTH END OF
THE VALLY IN THE AFTERNOON. GUSTY WINDS LOOKS TO DEVELOP OVER THE
NORTHERN MOUNTAINS AND COASTAL RANGE SUNDAY NIGHT WITH SOME GUSTS
BETWEEN 30 AND 40 MPH OVER THE FAVORED RIDGES AND THOUGH NORTH TO
NORTHEAST FACING CANYONS. THE FLOW WILL REVERSE ITSELF MONDAY NIGHT
INTO TUESDAY MORNING AS A STRONGER LOW PRESSURE AREA APPROACHES THE
REGION.
PATTERN BECOMES MORE INTERESTING AGAIN BY THE MIDDLE OF NEXT WEEK AS
MODELS CONTINUE TO ADVERTISE ANOTHER SYSTEM MOVING INTO THE REGION
TUESDAY NIGHT AND WEDNESDAY...SIMILAR IN STRENGTH TO THE ONE THAT
BROUGHT THE COOLER WEATHER AND SHOWERS LAST WEEK. SOME GUSTY WINDS
MAY DEVELOP OVER THE MOUNTAINS LATE TUESDAY AND EVENING AHEAD OF THE
LOW.
&&
.AVIATION...
VFR CONDS WITH CLEAR SKIES EXPECTED TO CONT OVER THE NXT 24 HRS. SW
WIND GUSTS TO 25 KT NEAR THE CARQUINEZ STRAIT TDA AND TNGT WITH LCL
ST OVER THE WRN DELTA UNTIL 18Z. LCL GUSTS TO 30 KT OVER NRN SIERRA
RIDGES THIS AFTN AND EVENING. GENERALLY LGT WINDS ELSW.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS65 KPSR 041302 AAA
AFDPSR
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PHOENIX AZ
602 AM MST SAT SEP 4 2010
.UPDATE...AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL BRING A CONTINUATION OF WELL ABOVE
NORMAL DAYTIME HIGH TEMPERATURES THROUGH SUNDAY. EXPECT TEMPERATURES
TO DRIFT LOWER NEXT WEEK AS THE HIGH PRESSURE SYSTEM MOVES OFF TO
THE EAST...WHILE A COUPLE OF RATHER STRONG LOW PRESSURE SYSTEMS MOVE
THROUGH THE INTERMOUNTAIN WEST. IN FACT...SLIGHTLY BELOW NORMAL
TEMPERATURES WILL PREVAIL ACROSS THE REGION WEDNESDAY THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF ISOLATED THUNDERSTORMS
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX TODAY THROUGH
NEXT TUESDAY.
&&
.DISCUSSION...
UPPER LEVEL HIGH PRESSURE THAT BROUGHT EXCESSIVE HEAT TO THE LOWER
DESERT ON FRIDAY WAS CENTERED JUST NORTHWEST OF LOS ANGELES THIS
MORNING...WITH RIDGE AXIS EXTENDING EAST ACROSS CENTRAL ARIZONA.
CENTER OF THE HIGH WILL MIGRATE SLOWLY EAST TODAY AND TONIGHT...THEN
WEAKEN SLOWLY AND MOVES TO SOUTHERN NEW MEXICO BY SUNDAY EVENING. AS
SUCH...WELL ABOVE NORMAL DAYTIME HIGHS WILL PERSIST THROUGH SUNDAY.
FORECAST SOUNDINGS INDICATE BOUNDARY LAYER TEMP WILL BE...ON
AVERAGE...1-3 F LOWER OVER THE LOWER DESERT TODAY COMPARED TO
FRIDAY...AND 1-2 F LOWER SUNDAY COMPARED TO TODAY. EXCESSIVE HEAT
WARNING...DRIVEN BY EXPECTED MAX TEMPS...WILL REMAIN IN EFFECT OVER
FAR SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA TODAY. AS EXPECTED...
ATMOSPHERE DID MOISTEN UP ACROSS SOUTH-CENTRAL AZ COMMENCING FRIDAY
AFTERNOON...AND SOME MOIST ADVECTION WILL OCCUR ACROSS WESTERN AZ
AND EXTREME SOUTHEAST CALIFORNIA TODAY. STILL...SFC DEW POINTS WILL
BE BELOW CLIMO...AND THAT...COMBINED WITH EXPECTED MID-LEVEL
WARMING...RESULTS IN DESERT SOUNDINGS PRETTY MUCH DEVOID OF CAPE.
CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGHER TERRAIN EAST OF
PHOENIX TODAY THROUGH LABOR DAY...BUT THATS ABOUT IT. RATHER STRONG
TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE INTERMOUNTAIN WEST...
MAINLY TO OUR NORTH...LATE SUNDAY INTO LABOR DAY...WHILE UPPER HIGH
MOVES WELL OFF TO OUR SOUTHEAST. AS RIDGE LOSES ITS GRIP ON THE
SOUTHWEST UNITED STATES...A COOLING TREND WILL COMMENCE...WITH LABOR
DAY HIGH TEMPS 4-6 DEGREES LOWER THAN WHAT OCCURS SUNDAY (EVEN
SO...MAX TEMPS LABOR DAY WILL BE A FEW DEGREES ABOVE CLIMO).
IN EXTENDED...ECMWF AND GFS AGREE THAT SOUTHWESTERLY FLOW WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A RATHER STRONG
TROUGH OF LOW PRESSURE FORECAST TO DEVELOP ALONG OR NEAR THE PACIFIC
COAST...THEN MOVE SLOWLY EAST ACROSS THE INTERMOUNTAIN WEST LATER IN
THE WEEK. FORECAST TEMPS SHOULD BE NEAR NORMAL TUESDAY...BUT LOWER
TO SLIGHTLY BELOW NORMAL THE REST OF THE WORK WEEK. IN ADVANCE OF
THE STRONG TROUGH...A WEAK WEATHER DISTURBANCE IS FORECAST TO BE
EJECTED EAST ACROSS SOUTHERN AZ/SONORA MEXICO ON TUESDAY...AND THIS
SYSTEM MAY TAP INTO ENOUGH MOISTURE TO INCREASE THE CHANCE FOR A
THUNDERSTORM MAINLY OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
WINDS WILL GENERALLY REMAIN OUT OF THE SOUTHEAST THROUGH THE DAY AND
INTO SUNDAY MORNING. BRIEF PERIOD OF WEST/NORTHWEST WINDS ARE
POSSIBLE DURING THE EVENING.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...
CLEAR SKY AND LIGHT WINDS THROUGH SATURDAY EVENING.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
BROAD TROUGHING WILL DOMINATE THE WEATHER PATTERN DURING THE
EXTENDED FORECAST PERIOD. TEMPERATURES WILL BE COOLING AS A RESULT.
SOME AFTERNOONS WILL BE BREEZY WITH WINDS GUSTING INTO THE 20 TO 30
MPH RANGE. VERY DRY AIR WILL ALSO SPREAD ACROSS MOST OF THE
SOUTHWEST PUSHING AFTERNOON HUMIDITY VALUES QUITE LOW THOUGH THERE
WILL BE DECENT OVERNIGHT RECOVERY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...DG
AVIATION...INIGUEZ
FIRE WEATHER...INIGUEZ
000
FXUS66 KEKA 041200
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
500 AM PDT SAT SEP 4 2010
.SYNOPSIS...A WEAK TROUGH ALOFT WILL MOVE OVER NORTHWEST CALIFORNIA
THIS WEEKEND...PRODUCING ROBUST NORTHERLY WINDS ALONG THE COAST AND
A COOLING TREND ACROSS THE INTERIOR.
&&
.DISCUSSION...STRATUS AND FOG WAS COVERING NEARLY THE ENTIRE COAST
EARLY THIS MORNING. THE LAYER HAS BEEN DEEPENING...WITH CEILINGS
LIFTING/VSBY IMPROVING AND CLOUDS PUSHING INTO THE EEL/VAN DUZEN
RIVER VALLEYS. THUS REMOVED THE MENTION OF DENSE FOG. NORTHERLY
WINDS WILL RAMP UP TODAY AND HELP TO SCOUR OUT THE LOW CLOUDS. AT
THE SAME TIME...THE NORTH WINDS WILL PACK THE LOW CLOUDS INTO THE
DELTA WHICH MAY BUILD BACK TO THE COAST. THUS WENT ONLY WITH PARTLY
CLOUDY SKIES THIS AFTERNOON AS A FEW AREAS MAY SEE LIMITED CLEARING.
OTHER THAN THE BRISK NORTHERLY WINDS IT IS LOOKING LIKE ANOTHER
FAIRLY NICE DAY ACROSS THE REGION. TEMPERATURES SHOULD CONTINUE ON
A DOWNWARD TREND...WITH MOSTLY 80S AND LOWER 90S OVER THE INTERIOR
AND WIND CHILLED LOWER 60S AT THE COAST. AFTER FRONTAL PASSAGE ON
SUNDAY...A RIDGE WILL BUILD INTO OREGON WHICH SHOULD PROMOTE
OFFSHORE FLOW AND A SLIGHT WARM UP. HOWEVER...ANOTHER SHORT-WAVE
TROUGH WILL DIG DOWN FROM THE GULF OF AK EARLY NEXT WEEK AND BRING
A SIGNIFICANT COOL DOWN ALONG WITH A CHANCE OF SHOWERS. THE WAY IT
IS LOOKING NOW...INTERIOR MAX TEMPS WILL STRUGGLE TO REACH THE MID
70S. GFS AND ECMWF INDICATES THIS SYSTEM WILL HAVE LIMITED OVER
WATER TRAJECTORY AND A WEAK SURFACE REFLECTION...SO THE PRECIP
CHANCES HAVE BEEN KEPT QUITE LOW. WE SHOULD SEE A FEW SHOWERS...MAINLY
OVER THE HIGHER ELEVATION AND VERY LIMITED DURATION RAIN AT LOWER
ELEVATIONS. AFTER THIS SHORT-WAVE MOVES THROUGH ON WED...ECMWF AND
GFS HAVE A FLAT RIDGE BUILDING WITH A COUPLE OF MINOR SHORT-WAVES
MOVING INTO THE PACIFIC NORTHWEST. STRONG WARMING IS UNLIKELY AND
EXPECT DRY WEATHER OVERALL WITH ONLY NICKEL-DIME CLIMATOLOGICAL
POPS. DJB
&&
.AVIATION...INCREASING NORTHERLY WINDS ALONG THE COAST WILL HELP
ERODE STRATUS TODAY. EXPECT THE STRATUS TO REMAIN MOST STUBBORN
AROUND THE HUMBOLDT BAY AND EEL RIVER DELTA. TH
&&
.MARINE...CURRENT FORECAST IS ON TRACK AS BUOY OBSERVATIONS HAVE
BEEN REPORTING A GRADUAL INCREASE IN NORTH WINDS...AND INCREASING
SHORT PERIOD SEAS EARLY THIS MORNING. EXPECT GALE GUSTS TO DEVELOP
ACROSS THE OUTER WATERS THIS AFTERNOON. THE GALES WILL PERSIST
THROUGH MONDAY NIGHT...AND LARGE STEEP SEAS WILL DOMINATE THE
WATERS. THESE HAZARDOUS SEAS WILL LIKELY MOVE THROUGH THE INNER
WATERS SOUTH OF CAPE MENDOCINO SUNDAY. THE SURFACE PRESSURE GRADIENT
WILL WEAKEN MONDAY AND THE MARINE CONDITIONS WILL IMPROVE. TH
&&
.EKA WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY FROM 10
AM THIS MORNING TO 3 AM PDT TUESDAY PZZ450. SMALL CRAFT ADVISORY
UNTIL 2 PM PDT THIS AFTERNOON PZZ470. GALE WARNING FROM 2 PM
THIS AFTERNOON TO 10 PM PDT MONDAY PZZ470. HAZARDOUS SEAS
WARNING FROM 2 PM THIS AFTERNOON TO 10 PM PDT MONDAY PZZ470.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 3 AM PDT TUESDAY
PZZ455. HAZARDOUS SEAS WARNING FROM 11 AM TO 11 PM PDT SUNDAY
PZZ455. SMALL CRAFT ADVISORY UNTIL 2 PM PDT THIS AFTERNOON
PZZ475. GALE WARNING FROM 2 PM THIS AFTERNOON TO 3 AM PDT
TUESDAY PZZ475. HAZARDOUS SEAS WARNING FROM 2 PM THIS AFTERNOON
TO 3 AM PDT TUESDAY PZZ475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
000
FXUS66 KLOX 041143
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
440 AM PDT SAT SEP 4 2010
...NEW AVIATION DISCUSSION...
.SYNOPSIS...
HIGH PRESSURE WILL KEEP THE WEATHER HOT ACROSS INLAND AREAS TODAY...
WITH RELATIVELY COOL WEATHER NEAR THE COAST. AN UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST ON SUNDAY...AND COOLING WILL BEGIN...
ALTHOUGH IT WILL STILL BE VERY WARM INLAND. MORE SIGNIFICANT COOLING
IS LIKELY MONDAY THROUGH WEDNESDAY AS AN UPPER LOW DROPS DOWN THE
COAST...AND NIGHT THROUGH MORNING CLOUDS WILL ADVANCE TO THE COASTAL
SLOPES. BELOW NORMAL TEMPERATURE WILL CONTINUE THROUGH FRIDAY.
&&
.SHORT TERM (TODAY-MON)...VERY SHALLOW MARINE LAYER THIS
MORNING...WITH AMDAR SOUNDINGS SHOWING THE BASE OF THE INVERSION
AROUND 300 FEET. THERE HAS BEEN SIGNIFICANT WARMING FROM 300 TO 1000
FEET DURING THE PAST 24 HOURS AS THE MARINE AIR HAS BEEN SQUASHED
BENEATH 300 FEET. N-S OFFSHORE PRES GRADS CONTD TO INCREASE...WHILE
W-E ONSHORE GRADS HAVE WEAKENED AND WERE NOW ALMOST NEUTRAL. SOME
LOCALLY GUSTY N WINDS WERE OCCURRING IN THE MTNS...INCLUDING THE
SANTA YNEZ RANGE...WHERE TEMPS WERE STILL NEAR 90 DEGREES AT THE
MONTECITO HILLS RAWS SENSOR AT 3 AM WITH A LIGHT NLY BREEZE. WHILE
THE EXTREMELY STRONG INVERSION WILL LIKELY MAKE FOR SLOW AND/0R
INCOMPLETE CLEARING NEAR THE IMDT BEACHES S OF PT CONCEPTION...THE
FACT THAT THE INVERSION HAS LOWERED SO MUCH...AND SO MUCH WARMING
HAS OCCURRED JUST ABOVE THE SFC WILL PROBABLY ALLOW FOR SEVERAL
DEGREES OF WARMING ACROSS INLAND SECTIONS OF THE CSTL PLAIN. EXPECT
INLAND SECTIONS OF THE LOS ANGELES COUNTY COASTAL PLAIN TO HAVE A
GOOD CHANCE OF REACHING OR EXCEEDING 90 DEGREES TODAY. TEMPS IN
THE HILLS FROM ABOVE BEVERLY HILLS THROUGH THE HOLLYWOOD HILLS
SHOULD HAVE NO PROBLEM REACHING 100 DEGREES TODAY.
ALSO EXPECT WARMING IN THE VLYS...ANTELOPE VALLEY AND LOWER MOUNTAIN
ELEVATIONS WHERE MOST LOCATIONS WILL REACH 100 DEGREES...AND THE
HOTTEST LOCATIONS WILL HAVE HIGHS ABOVE 105 DEGREES. CONTINUED VERY
DRY CONDITIONS TODAY WILL ACTUALLY MAKE HEAT INDEX VALUES LOWER THAN
THE ACTUAL TEMPERATURE. ON THE FLIP SIDE...HOT AND VERY DRY
CONDITIONS...ALONG WITH SOME LOCALLY GUSTY WINDS...WILL MAKE FOR
HIGH FIRE DANGER IN THE MOUNTAINS OF LOS ANGELES COUNTY TODAY.
THE UPPER HIGH WILL BEGIN TO WEAKEN AND SHIFT EWD TONIGHT AND SUNDAY
AS A TROUGH MOVES INTO THE PAC NW. LOW CLOUDS MAY PUSH A BIT FARTHER
INLAND ACROSS THE CSTL PLAIN TONIGHT/SUN MORNING ACROSS L.A. AND VTU
COUNTIES...WITH WDSPRD CLOUDS EXPECTED ON THE CENTRAL CST.
HOWEVER...N-S GRADS ACROSS SBA COUNTY COULD HOLD STRATUS AT BAY...OR
AT LEAST DELAY THE ONSET OF ANY CLOUDS UNTIL NEAR DAYBREAK ON
SUNDAY. N-S GRADS WILL LIKELY BE STRONG ENOUGH TO PRODUCE SOME
LOCALLY GUSTY WINDS THRU AND BELOW PASSES AND CANYONS OF THE SANTA
YNEZ RANGE...BUT WINDS SHOULD STAY BELOW ADVISORY LEVELS. THE MARINE
LAYER SHOULD REMAIN SHALLOW ENOUGH SO THAT THERE MAY BE SOME DENSE
FOG ON THE CSTL PLAIN...AND IT APPEARS THAT CLOUDS WILL STAY OUT OF
THE VLYS. LOWERING HEIGHTS/THICKNESSES AND STRONGER ONSHORE GRADS
WILL LIKELY LEAD TO SEVERAL DEGREES OF COOLING ACROSS MUCH OF THE
REGION ON SUN...WITH COOLING ON THE ORDER OF 6 TO 12 DEGREES LIKELY
IN THE VLYS AND ACROSS INTERIOR SECTIONS OF THE CSTL PLAIN.
STILL...TEMPS SHOULD BE NEAR OR A BIT ABOVE NORMAL IN INLAND AREAS.
N-S WILL PRODUCE ANOTHER ROUND OF GUSTY WINDS THRU AND BELOW PASSES
AND CANYONS OF SRN SBA COUNTY AND POSSIBLY THRU THE I-5 CORRIDOR
SUNDAY NIGHT...AND THE WRF SHOWS A WELL DEVELOPED EDDY CIRCULATION
DEVELOPING. THIS SHOULD HELP DEEPEN THE MARINE LAYER S OF PT
CONCEPTION...AND EXPECT WDSPRD CLOUDS IN CSTL SXNS OF L.A. AND VTU
COUNTIES...LIKELY SPREADING INTO MANY VALLEY AREAS LATE SUN
NIGHT/MON MORNING. WITH THE NLY GRADS...IT MAY BE TOUGH FOR CLOUDS
TO REACH SRN SBA COUNTY UNTIL DAYBREAK ON MONDAY. AND...PRESUMABLY
BECAUSE OF THE GRADS...THE WRF SHOWS LESS IN THE WAY OF CLOUDS ON
THE CENTRAL COAST AS WELL. EXPECT ANOTHER 6 TO 10 DEGREES OF COOLING
IN MOST AREAS ON MONDAY...WITH THE BEST COOLING IN THE VLYS.
.LONG TERM (TUE-FRI)...AN UPPER LOW WILL DROP SWD DOWN THE WEST
COAST TUE THRU WED...WITH A BROAD TROUGH ACROSS THE REGION GRADUALLY
SHARPENING UP. LOWERING HEIGHTS AND THICKNESSES...AND COOLING AT 850
AND 950 MB...ALONG WITH INCREASING ONSHORE FLOW AND A DEEPENING
MARINE LAYER WILL LIKELY CONTINUE TO PRODUCE SOME COOLING EACH DAY.
ALTHOUGH THE UPPER LOW WILL MOVE INTO THE NRN ROCKIES ON
THU...STRONGLY CYCLONIC FLOW ALOFT WILL LINGER ACROSS THE REGION.
EXPECT THE MARINE LAYER TO DEEPEN ENOUGH TO PUSH CLOUDS TO THE
CSTL SLOPES FOR TUE NIGHT AND WED NIGHT...AND THERE WILL PROBABLY BE
SOME DRIZZLE THOSE NIGHTS AS WELL. TEMPS WILL BE WELL BELOW NORMAL
ACROSS THE REGION TUE THRU THU. SOME WARMING MAY BEGIN ON FRI AS THE
TROUGH MOVES EWD AND HEIGHTS BEGIN TO REBOUND.
&&
.AVIATION...04/1200Z.
VERY LOW CONFIDENCE IN THE 12Z COASTAL TAFS IN CONTRAST TO HIGH
CONFIDENCE IN THE VALLEY TAFS. A SHALLOW MARINE LAYER OF AROUND 700
FEET WITH LIFR CONDITIONS IS STRUGGLING TO MAINTAIN A PRESENCE IN
THE VICINITY OF THE IMMEDIATE COAST AMIDST AN INCREASING ONSLAUGHT
OF OFFSHORE TRENDS IN THE PRESSURE GRADIENTS. THE RESULT SEEMS TO BE
CAUSING THE LOW CLOUDS AND DENSE FOG TO OSCILLATE BACK AND FORTH AT
THE COAST AND THE COASTAL TAF SITES ARE SHOWING LITTLE IN THE WAY OF
TEMPORAL CONSISTENCY. THE VALLEY TAFS WILL REMAIN VFR THROUGH THE
DAY.
KLAX...VERY LOW CONFIDENCE IN THE 12Z TAF WITH INTERMITTENT LIFR
CONDITIONS INTERSPERSED WITH OCCASIONAL VFR CONDITIONS. ALMOST NO
TEMPORAL CONSISTENCY.
KBUR...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE DAY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...BRUNO
AVIATION...SWEET
SYNOPSIS...
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KLOX 041122
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
343 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE WILL KEEP THE WEATHER HOT ACROSS INLAND AREAS TODAY...
WITH RELATIVELY COOL WEATHER NEAR THE COAST. AN UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST ON SUNDAY...AND COOLING WILL BEGIN...
ALTHOUGH IT WILL STILL BE VERY WARM INLAND. MORE SIGNIFICANT COOLING
IS LIKELY MONDAY THROUGH WEDNESDAY AS AN UPPER LOW DROPS DOWN THE
COAST...AND NIGHT THROUGH MORNING CLOUDS WILL ADVANCE TO THE COASTAL
SLOPES. BELOW NORMAL TEMPERATURE WILL CONTINUE THROUGH FRIDAY.
&&
.SHORT TERM (TODAY-MON)...VERY SHALLOW MARINE LAYER THIS
MORNING...WITH AMDAR SOUNDINGS SHOWING THE BASE OF THE INVERSION
AROUND 300 FEET. THERE HAS BEEN SIGNIFICANT WARMING FROM 300 TO 1000
FEET DURING THE PAST 24 HOURS AS THE MARINE AIR HAS BEEN SQUASHED
BENEATH 300 FEET. N-S OFFSHORE PRES GRADS CONTD TO INCREASE...WHILE
W-E ONSHORE GRADS HAVE WEAKENED AND WERE NOW ALMOST NEUTRAL. SOME
LOCALLY GUSTY N WINDS WERE OCCURRING IN THE MTNS...INCLUDING THE
SANTA YNEZ RANGE...WHERE TEMPS WERE STILL NEAR 90 DEGREES AT THE
MONTECITO HILLS RAWS SENSOR AT 3 AM WITH A LIGHT NLY BREEZE. WHILE
THE EXTREMELY STRONG INVERSION WILL LIKELY MAKE FOR SLOW AND/0R
INCOMPLETE CLEARING NEAR THE IMDT BEACHES S OF PT CONCEPTION...THE
FACT THAT THE INVERSION HAS LOWERED SO MUCH...AND SO MUCH WARMING
HAS OCCURRED JUST ABOVE THE SFC WILL PROBABLY ALLOW FOR SEVERAL
DEGREES OF WARMING ACROSS INLAND SECTIONS OF THE CSTL PLAIN. EXPECT
INLAND SECTIONS OF THE LOS ANGELES COUNTY COASTAL PLAIN TO HAVE A
GOOD CHANCE OF REACHING OR EXCEEDING 90 DEGREES TODAY. TEMPS IN
THE HILLS FROM ABOVE BEVERLY HILLS THROUGH THE HOLLYWOOD HILLS
SHOULD HAVE NO PROBLEM REACHING 100 DEGREES TODAY.
ALSO EXPECT WARMING IN THE VLYS...ANTELOPE VALLEY AND LOWER MOUNTAIN
ELEVATIONS WHERE MOST LOCATIONS WILL REACH 100 DEGREES...AND THE
HOTTEST LOCATIONS WILL HAVE HIGHS ABOVE 105 DEGREES. CONTINUED VERY
DRY CONDITIONS TODAY WILL ACTUALLY MAKE HEAT INDEX VALUES LOWER THAN
THE ACTUAL TEMPERATURE. ON THE FLIP SIDE...HOT AND VERY DRY
CONDITIONS...ALONG WITH SOME LOCALLY GUSTY WINDS...WILL MAKE FOR
HIGH FIRE DANGER IN THE MOUNTAINS OF LOS ANGELES COUNTY TODAY.
THE UPPER HIGH WILL BEGIN TO WEAKEN AND SHIFT EWD TONIGHT AND SUNDAY
AS A TROUGH MOVES INTO THE PAC NW. LOW CLOUDS MAY PUSH A BIT FARTHER
INLAND ACROSS THE CSTL PLAIN TONIGHT/SUN MORNING ACROSS L.A. AND VTU
COUNTIES...WITH WDSPRD CLOUDS EXPECTED ON THE CENTRAL CST.
HOWEVER...N-S GRADS ACROSS SBA COUNTY COULD HOLD STRATUS AT BAY...OR
AT LEAST DELAY THE ONSET OF ANY CLOUDS UNTIL NEAR DAYBREAK ON
SUNDAY. N-S GRADS WILL LIKELY BE STRONG ENOUGH TO PRODUCE SOME
LOCALLY GUSTY WINDS THRU AND BELOW PASSES AND CANYONS OF THE SANTA
YNEZ RANGE...BUT WINDS SHOULD STAY BELOW ADVISORY LEVELS. THE MARINE
LAYER SHOULD REMAIN SHALLOW ENOUGH SO THAT THERE MAY BE SOME DENSE
FOG ON THE CSTL PLAIN...AND IT APPEARS THAT CLOUDS WILL STAY OUT OF
THE VLYS. LOWERING HEIGHTS/THICKNESSES AND STRONGER ONSHORE GRADS
WILL LIKELY LEAD TO SEVERAL DEGREES OF COOLING ACROSS MUCH OF THE
REGION ON SUN...WITH COOLING ON THE ORDER OF 6 TO 12 DEGREES LIKELY
IN THE VLYS AND ACROSS INTERIOR SECTIONS OF THE CSTL PLAIN.
STILL...TEMPS SHOULD BE NEAR OR A BIT ABOVE NORMAL IN INLAND AREAS.
N-S WILL PRODUCE ANOTHER ROUND OF GUSTY WINDS THRU AND BELOW PASSES
AND CANYONS OF SRN SBA COUNTY AND POSSIBLY THRU THE I-5 CORRIDOR
SUNDAY NIGHT...AND THE WRF SHOWS A WELL DEVELOPED EDDY CIRCULATION
DEVELOPING. THIS SHOULD HELP DEEPEN THE MARINE LAYER S OF PT
CONCEPTION...AND EXPECT WDSPRD CLOUDS IN CSTL SXNS OF L.A. AND VTU
COUNTIES...LIKELY SPREADING INTO MANY VALLEY AREAS LATE SUN
NIGHT/MON MORNING. WITH THE NLY GRADS...IT MAY BE TOUGH FOR CLOUDS
TO REACH SRN SBA COUNTY UNTIL DAYBREAK ON MONDAY. AND...PRESUMABLY
BECAUSE OF THE GRADS...THE WRF SHOWS LESS IN THE WAY OF CLOUDS ON
THE CENTRAL COAST AS WELL. EXPECT ANOTHER 6 TO 10 DEGREES OF COOLING
IN MOST AREAS ON MONDAY...WITH THE BEST COOLING IN THE VLYS.
.LONG TERM (TUE-FRI)...AN UPPER LOW WILL DROP SWD DOWN THE WEST
COAST TUE THRU WED...WITH A BROAD TROUGH ACROSS THE REGION GRADUALLY
SHARPENING UP. LOWERING HEIGHTS AND THICKNESSES...AND COOLING AT 850
AND 950 MB...ALONG WITH INCREASING ONSHORE FLOW AND A DEEPENING
MARINE LAYER WILL LIKELY CONTINUE TO PRODUCE SOME COOLING EACH DAY.
ALTHOUGH THE UPPER LOW WILL MOVE INTO THE NRN ROCKIES ON
THU...STRONGLY CYCLONIC FLOW ALOFT WILL LINGER ACROSS THE REGION.
EXPECT THE MARINE LAYER TO DEEPEN ENOUGH TO PUSH CLOUDS TO THE
CSTL SLOPES FOR TUE NIGHT AND WED NIGHT...AND THERE WILL PROBABLY BE
SOME DRIZZLE THOSE NIGHTS AS WELL. TEMPS WILL BE WELL BELOW NORMAL
ACROSS THE REGION TUE THRU THU. SOME WARMING MAY BEGIN ON FRI AS THE
TROUGH MOVES EWD AND HEIGHTS BEGIN TO REBOUND.
&&
.AVIATION...WILL BE ISSUED WITH THE 12Z TAFS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
&&
$$
PUBLIC...BRUNO
AVIATION...SWEET
SYNOPSIS...
WWW.WEATHER.GOV/LOSANGELES
000
FXUS66 KMTR 041122
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
422 AM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 2:45 AM PDT SATURDAY...LATEST SATL FOG PRODUCT
AND SURFACE OBSERVATIONS SHOW LOW CLOUDS AND FOG HAVE PUSHED INTO
THE NORTH BAY VALLEYS...INTO SAN FRANCISCO BAY AND SAN PABLO BAY
AND INLAND FROM MONTEREY BAY TO HOLLISTER AND WELL DOWN THE SALINAS
VALLEY. ONSHORE GRADIENTS ARE ABOUT THE SAME AS 24 HRS AGO AT
CLOSE TO 3 MB. MARINE INVERSION RUNNING CLOSE TO 1000 FT THIS AM.
TODAY`S HIGHS SHOULD BE VERY SIMILAR TO YESTERDAYS EXCEPT A FEW
DEGREES COOLER COAST AND COASTAL VALLEYS. NORTH BAY INTERIOR VALLEYS
WILL SEE SOME SLIGHT COOLING TODAY BUT INTERIOR LOCATIONS OF THE EAST
BAY AND SOUTHERN SALINAS VALLEYS MAY SEE A FEW DEGREES OF WARMING.
UPPER TROUGH MOVING INTO THE PACNW APPEARS TO BE LIFTING MORE TO
THE NE THEN MODELS HAD EARLIER PREDICTED. THIS WILL KEEP HEIGHTS
AND TEMPS OVER OUR AREA NEAR STATUS QUO EXCEPT IN SOUTHERN QUARTER
OF THE DISTRICT WHERE 850 TEMPS COOL SLIGHTLY. SO EXPECT LITTLE
TEMPERATURE CHANGE SUNDAY EXCEPT SOUTHERN SECTIONS OF THE SALINAS
VALLEY AND SURROUNDING HILLS. MODELS ARE INDICATING WEAK OFFSHORE
FLOW TO BEGIN AS EARLY AS LATE SUNDAY WITH LOW CLOUDS PUSHED OFF THE
COAST AND WILL REMAIN WELL AWAY FROM THE COAST MONDAY.
FAIR SKIES SUNDAY NIGHT INTO LABOR DAY WITH THE WEAK OFFSHORE
FLOW KEEPING SKIES CLEAR ALL DAY MONDAY WITH TEMPERATURES WARMING AT
THE COAST AND COASTAL VALLEYS. MAY SEE SOME BREEZY CONDITIONS IN THE
NORTH BAY HILLS OVERNIGHT SUNDAY INTO MONDAY MORNING. THESE WINDS
WILL HELP WARM COASTAL AREAS WHERE NEAR 80 DEGREES IS POSSIBLE IN
DOWNTOWN SAN FRANCISCO LABOR DAY WITH 80S AND 90S THE RULE MOST OTHER
LOCATIONS. THIS WARM-UP WILL BE VERY BRIEF SO ENJOY THE LABOR HOLIDAY
WARMTH AND SUNNY SKIES.
EXTENDED...TUESDAY WILL SEE A DRAMATIC DROP IN TEMPERATURES AS A
VIGOROUS UPPER TROUGH DIGS SOUTH FROM CANADA DOWN THE COAST OF WA
AND OR. THIS TROUGH WILL RAPIDLY DEEPEN THE MARINE LAYER AND ALLOW
LOW CLOUDS AND FOG TO QUICKLY FORM OVER NIGHT MONDAY MOVING WELL
INLAND BY TUESDAY MORNING. FIFTEEN TO 25 DEGREE TEMPERATURE DROPS
WILL BE THE NORM FOR TUE FROM WHAT WILL OCCUR LABOR DAY. THESE
WILL BE 10 TO 15 DEGREES BELOW NORMAL FOR EARLY SEPTEMBER. THESE
COOL TEMPERATURES WILL CONTINUE WED INTO THURSDAY AS THE UPPER
TROUGH WILL BE SLOW TO MOVE EAST UNTIL THURSDAY. A SLOW WARMING
TREND WILL BEGIN THURSDAY MAINLY INTERIOR VALLEYS AS A BAGGY WEAK
TROUGH REMAINS OVER THE WEST COAST INTO NEXT WEEKEND. TEMPERATURES
WILL REMAIN BELOW NORMAL THROUGH THE EXTENDED PERIOD WITH NIGHT
AND MORNING COASTAL LOW CLOUDS MOVING WELL INLAND NIGHTS AND
MORNINGS.
&&
.AVIATION...AS OF 4:22 AM PDT SATURDAY...SATELLITE IMAGERY AND
SURFACE OBSERVATIONS INDICATE LOW CLOUDS OVER ALL TERMINAL SITES AT
THIS TIME WITH CEILINGS RANGING FROM A FEW HUNDRED FEET TO 1000
FEET. THE MARINE LAYER DEPTH HAS RAMPED UP TO ABOUT 1400 FEET PER
THE FORT ORD PROFILER...AND THE ONSHORE SURFACE PRESSURE GRADIENT
HAS INCREASED TO NEARLY 3 MB FROM SFO TO SAC. EXPECT CEILINGS TO
BREAK UP BY 18Z MOST AREAS.
&&
.VICINITY OF KSFO...IFR CIGS THRU 18Z. GUSTY NORTHWEST WINDS WILL
ONCE AGAIN DEVELOP AROUND 21Z WITH GUSTS TO 22 KNOTS.
.KSFO BRIDGE APPROACH...IFR CIGS OVER THE APPROACH. VFR RETURNING BY
18Z.
.MRY BAY AREA TERMINALS...LIFR CIGS THRU 17Z AND LOCAL IFR
VISIBILITIES THRU 14Z. LOW CLOUDS AND FOG CLEARING TO THE COAST
BETWEEN 18Z AND 19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.AFTERNOON...SCA...NORTHERN OUTER WATERS AND SAN
FRANCISCO BAY.
&&
$$
PUBLIC FORECAST: REYNOLDS
AVIATION/MARINE: SSA
000
FXUS65 KPSR 041115
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
414 AM MST SAT SEP 4 2010
.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL BRING A CONTINUATION OF WELL ABOVE
NORMAL DAYTIME HIGH TEMPERATURES THROUGH SUNDAY. EXPECT TEMPERATURES
TO DRIFT LOWER NEXT WEEK AS THE HIGH PRESSURE SYSTEM MOVES OFF TO
THE EAST...WHILE A COUPLE OF RATHER STRONG LOW PRESSURE SYSTEMS MOVE
THROUGH THE INTERMOUNTAIN WEST. IN FACT...SLIGHTLY BELOW NORMAL
TEMPERATURES WILL PREVAIL ACROSS THE REGION WEDNESDAY THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF ISOLATED THUNDERSTORMS
ACROSS THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX TODAY THROUGH
NEXT TUESDAY.
&&
.DISCUSSION...
UPPER LEVEL HIGH PRESSURE THAT BROUGHT EXCESSIVE HEAT TO THE LOWER
DESERT ON FRIDAY WAS CENTERED JUST NORTHWEST OF LOS ANGELES THIS
MORNING...WITH RIDGE AXIS EXTENDING EAST ACROSS CENTRAL ARIZONA.
CENTER OF THE HIGH WILL MIGRATE SLOWLY EAST TODAY AND TONIGHT...THEN
WEAKEN SLOWLY AND MOVES TO SOUTHERN NEW MEXICO BY SUNDAY EVENING. AS
SUCH...WELL ABOVE NORMAL DAYTIME HIGHS WILL PERSIST THROUGH SUNDAY.
FORECAST SOUNDINGS INDICATE BOUNDARY LAYER TEMP WILL BE...ON
AVERAGE...1-3 F LOWER OVER THE LOWER DESERT TODAY COMPARED TO
FRIDAY...AND 1-2 F LOWER SUNDAY COMPARED TO TODAY. EXCESSIVE HEAT
WARNING...DRIVEN BY EXPECTED MAX TEMPS...WILL REMAIN IN EFFECT OVER
FAR SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA TODAY. AS EXPECTED...
ATMOSPHERE DID MOISTEN UP ACROSS SOUTH-CENTRAL AZ COMMENCING FRIDAY
AFTERNOON...AND SOME MOIST ADVECTION WILL OCCUR ACROSS WESTERN AZ
AND EXTREME SOUTHEAST CALIFORNIA TODAY. STILL...SFC DEW POINTS WILL
BE BELOW CLIMO...AND THAT...COMBINED WITH EXPECTED MID-LEVEL
WARMING...RESULTS IN DESERT SOUNDINGS PRETTY MUCH DEVOID OF CAPE.
CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGHER TERRAIN EAST OF
PHOENIX TODAY THROUGH LABOR DAY...BUT THATS ABOUT IT. RATHER STRONG
TROUGH OF LOW PRESSURE MOVES EAST ACROSS THE INTERMOUNTAIN WEST...
MAINLY TO OUR NORTH...LATE SUNDAY INTO LABOR DAY...WHILE UPPER HIGH
MOVES WELL OFF TO OUR SOUTHEAST. AS RIDGE LOSES ITS GRIP ON THE
SOUTHWEST UNITED STATES...A COOLING TREND WILL COMMENCE...WITH LABOR
DAY HIGH TEMPS 4-6 DEGREES LOWER THAN WHAT OCCURS SUNDAY (EVEN
SO...MAX TEMPS LABOR DAY WILL BE A FEW DEGREES ABOVE CLIMO).
IN EXTENDED...ECMWF AND GFS AGREE THAT SOUTHWESTERLY FLOW WILL
PREVAIL OVER THE SOUTHWEST UNITED STATES...WITH A RATHER STRONG
TROUGH OF LOW PRESSURE FORECAST TO DEVELOP ALONG OR NEAR THE PACIFIC
COAST...THEN MOVE SLOWLY EAST ACROSS THE INTERMOUNTAIN WEST LATER IN
THE WEEK. FORECAST TEMPS SHOULD BE NEAR NORMAL TUESDAY...BUT LOWER
TO SLIGHTLY BELOW NORMAL THE REST OF THE WORK WEEK. IN ADVANCE OF
THE STRONG TROUGH...A WEAK WEATHER DISTURBANCE IS FORECAST TO BE
EJECTED EAST ACROSS SOUTHERN AZ/SONORA MEXICO ON TUESDAY...AND THIS
SYSTEM MAY TAP INTO ENOUGH MOISTURE TO INCREASE THE CHANCE FOR A
THUNDERSTORM MAINLY OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX AND KIWA...
CONVECTION APPEARS OVER FOR TONIGHT...JUST A FEW MID LEVEL DEBRIS
CLOUDS EXPECTED OVER THE CENTRAL DESERTS THROUGH THE EARLY MORNING
HOURS. MOST BASES AOA 14KT FEET. GUSTY SELY WINDS IN EXCESS OF 20KT
POSSIBLE THRU ABOUT 05Z...OTHERWISE EXPECT WINDS TO BE GENLY
SOUTHEAST AT KPHX/KIWA INTO THE AFTERNOON HOURS SATURDAY...BETWEEN
5-15 MPH...AS E-W SURFACE GRADIENTS REMAIN TIGHT. EXPECT SOME HIGH
BASED CU TO DEVELOP AGAIN SATURDAY FROM PHOENIX EASTWARD BUT ANY
THREAT FOR CONVECTION SHOULD AGAIN BE MOSTLY TIED TO HIGHER TERRAIN
TO OUR EAST.
SOUTHEAST CALIFORNIA...SOUTHWEST AND INCLUDING KIPL...KBLH...CLEAR
SKY AND LIGHT WINDS THROUGH SATURDAY EVENING.
DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
BROAD TROUGHING WILL DOMINATE THE WEATHER PATTERN DURING THE
EXTENDED FORECAST PERIOD. TEMPERATURES WILL BE COOLING AS A RESULT.
SOME AFTERNOONS WILL BE BREEZY WITH WINDS GUSTING INTO THE 20 TO 30
MPH RANGE. VERY DRY AIR WILL ALSO SPREAD ACROSS MOST OF THE
SOUTHWEST PUSHING AFTERNOON HUMIDITY VALUES QUITE LOW THOUGH THERE
WILL BE DECENT OVERNIGHT RECOVERY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TODAY
AZZ020-021-025-026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TODAY
CAZ031>033.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...DG
AVIATION...CB
FIRE WEATHER...INIGUEZ
000
FXUS66 KHNX 041101 CCA
AFDHNX
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
359 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE OVERHEAD WILL KEEP TEMPERATURES AROUND 6-12 DEGREES
ABOVE AVERAGE TODAY. A LOW PRESSURE SYSTEM WILL THEN MOVE THROUGH
THE REGION...BRINGING COOLING TEMPERATURES THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.DISCUSSION...
A STRONG UPPER LEVEL RIDGE DRAPED ACROSS THE CENTRAL CALIFORNIA
INTERIOR HAS PRODUCED SOME HOT CONDITIONS FOR THE LAST COUPLE OF
DAYS...WITH TEMPERATURES RUNNING WELL ABOVE SEASONAL AVERAGES. A
TROUGH DROPPING SOUTH INTO THE PACIFIC NORTHWEST IS BEGINNING TO
FLATTEN THE RIDGE AND SHOULD LOWER TEMPERATURES JUST A DEGREE OR
SO AT MOST LOCATIONS THIS AFTERNOON.
A MORE NOTABLE COOLING TREND WILL ENSUE BEGINNING SUNDAY AS
THE LOW PRESSURE TROUGH PUSHES INTO CALIFORNIA. BY
MONDAY...TEMPERATURES WILL BE BACK TO AROUND CLIMO...CONTINUING
DOWNWARD INTO THE MIDDLE OF NEXT WEEK AS ADDITIONAL PASSING
SHORTWAVE ENERGY BRINGS MORE COOLING TO THE REGION. EXPECT
TEMPERATURES DOWN AS MUCH AS 10-15 DEGREES BELOW CLIMO BY
WEDNESDAY/THURSDAY.
MODELS REMAIN PRETTY DRY WITH THE PASSING SYSTEMS...THOUGH THE ECMWF
CONTINUES TO SPIT OUT A LITTLE QPF OVER THE SIERRA WEDNESDAY INTO
THURSDAY. A SLIGHT CHANCE FOR PRECIP CAN NOT BE RULED OUT SO POPS
HAVE BEEN NUDGED SLIGHTLY UPWARD IN THE SIERRA NORTH OF KINGS CANYON
FOR MIDWEEK.
MODELS ARE SIMILAR IN KEEPING A BROAD TROUGHINESS OVER THE REGION
FOR THE END OF NEXT WEEK WHICH SHOULD MODERATE TEMPERATURE
RECOVERY...KEEPING CONDITIONS A BIT COOLER THAN CLIMO.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL UNDER GENERALLY CLEAR SKIES ACROSS THE
CENTRAL CALIFORNIA INTERIOR THROUGH 12Z SUNDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...JEB
AVN/FW...DURFEE
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KHNX 041059
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
359 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE OVERHEAD WILL KEEP TEMPERATURES AROUND 6-12 DEGREES
ABOVE AVERAGE TODAY. A LOW PRESSURE SYSTEM WILL THEN MOVE THROUGH
THE REGION...BRINGING COOLING TEMPERATURES THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.DISCUSSION...
A STRONG UPPER LEVEL TROUGH DRAPED ACROSS THE CENTRAL CALIFORNIA
INTERIOR HAS PRODUCED SOME HOT CONDITIONS FOR THE LAST COUPLE OF
DAYS...WITH TEMPERATURES RUNNING WELL ABOVE SEASONAL AVERAGES. A
TROUGH DROPPING SOUTH INTO THE PACIFIC NORTHWEST IS BEGINNING TO
FLATTEN THE RIDGE AND SHOULD LOWER TEMPERATURES JUST A DEGREE OR
SO AT MOST LOCATIONS THIS AFTERNOON.
A MORE NOTABLE COOLING TREND WILL ENSUE BEGINNING SUNDAY AS
THE LOW PRESSURE TROUGH PUSHES INTO CALIFORNIA. BY
MONDAY...TEMPERATURES WILL BE BACK TO AROUND CLIMO...CONTINUING
DOWNWARD INTO THE MIDDLE OF NEXT WEEK AS ADDITIONAL PASSING
SHORTWAVE ENERGY BRINGS MORE COOLING TO THE REGION. EXPECT
TEMPERATURES DOWN AS MUCH AS 10-15 DEGREES BELOW CLIMO BY
WEDNESDAY THURSDAY. MODELS REMAIN PRETTY DRY WITH THE PASSING
SYSTEMS THOUGH THE ECMWF CONTINUES TO SPIT OUT A LITTLE QPF OVER
THE SIERRA WEDNESDAY INTO THURSDAY. A SLIGHT CHANCE FOR PRECIP CAN
NOT BE RULED OUT SO POPS HAVE BEEN NUDGED SLIGHTLY UPWARD IN THE
SIERRA NORTH OF KINGS CANYON FOR MIDWEEK.
MODELS ARE SIMILAR IN KEEPING A BROAD TROUGHINESS OVER THE REGION
FOR THE END OF NEXT WEEK WHICH SHOULD MODERATE TEMPERATURE
RECOVERY...KEEPING CONDITIONS A BIT COOLER THAN CLIMO.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL UNDER GENERALLY CLEAR SKIES ACROSS THE
CENTRAL CALIFORNIA INTERIOR THROUGH 12Z SUNDAY.
&&
.AIR QUALITY ISSUES...
PLEASE SEE SFOAQAHNX
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...JEB
AVN/FW...DURFEE
SYNOPSIS...TLM
WEATHER.GOV/HANFORD
000
FXUS66 KSGX 041048
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
345 AM PDT SAT SEP 4 2010
.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BRING ANOTHER HOT DAY TO INLAND AREAS. NEAR
THE COAST IT WILL BE COOLER FROM A SHALLOW MARINE LAYER THAT WILL
ALSO RESULT IN AREAS OF DENSE FOG THIS MORNING. NEXT WEEK A LOW
PRESSURE TROUGH WILL DEEPEN ALONG THE WEST COAST BRINGING COOLER
WEATHER AND A DEEPER MARINE LAYER.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
SIMILAR TO YESTERDAY...A SHALLOW MARINE LAYER HAS RESULTED IN A
VERY LOW CLOUD DECK AT THE COAST THIS MORNING. AREAS OF DENSE FOG
NEAR THE COAST WILL LINGER AT A FEW OF THE BEACHES INTO THE
AFTERNOON.
FARTHER INLAND IT WILL BE ANOTHER SUNNY...HOT DAY WITH TRIPLE DIGIT
HIGHS IN THE VALLEYS...FOOTHILLS AND DESERTS. THE AIRMASS REMAINS
INCREDIBLY DRY ABOVE THE MARINE LAYER WITH DEWPOINTS ONLY IN THE 30S
AND 40S WHICH WILL RESULT IN ANOTHER AFTERNOON OF VERY LOW
HUMIDITIES. WHILE IT WILL BE QUITE HOT...THE HEAT INDEX VALUES WILL
BE A FEW DEGREES LOWER THAN THE ACTUAL TEMPS AND NOT MEET OUR
EXCESSIVE HEAT WARNING CRITERIA.
THE DOMINATING UPPER RIDGE RESPONSIBLE FOR THE HOT WEATHER WILL
WEAKEN ON SUNDAY AHEAD OF A DEVELOPING WEST COAST TROUGH. ONSHORE
FLOW WILL STRENGTHEN SUNDAY AFTERNOON AND IT WILL BE WINDIER IN THE
MOUNTAINS AND DESERTS WITH WINDS FROM 15 TO 25 MPH. PEAK WINDS OF
30-35 MPH ARE FORECAST OVER AND ON THE LEE SIDE OF THE RIDGES ON THE
DOWNSLOPE SIDE OF THE MOUNTAINS. WINDS WILL BE LIGHTER MONDAY AND
MAY SHIFT BRIEFLY OFFSHORE AS THE PRESSURE GRADIENTS REVERSE AND THE
WINDS ALOFT TURN NORTHEAST FOR A SHORT TIME.
ON WEDNESDAY...A REINFORCING SHORTWAVE WILL DEEPEN THE TROUGH AND
BRING FURTHER COOLING AND ANOTHER BOUT OF GUSTY WINDS IN THE
MOUNTAINS AND DESERTS. THE STRONG ONSHORE FLOW WILL SUBSTANTIALLY
DEEPEN THE MARINE LAYER SO THAT BY THURSDAY MORNING THE MARINE LAYER
CLOUDS WILL BLANKET THE VALLEYS.
SOME WARMING IS FORECAST THURSDAY AND FRIDAY IN RESPONSE TO
INCREASING HEIGHTS AND THICKNESSES BEHIND THE DEPARTING SHORTWAVE.
&&
.AVIATION...
040854Z...AREAS OF LIFR CIGS/VIS EXPECTED ALONG THE COAST THROUGH
16Z THIS MORNING WITH TOPS BELOW FL008. CONFIDENCE LOW ON EXTENT AND
ONSET AT TAF SITES BUT EXPECT THERE WILL BE LOCAL DENSE FOG ALONG
THE COASTAL STRIP BY SUN UP AND KSAN MAY FALL BELOW LANDING MINIMUMS
FOR A TIME. ANY CIGS/VIS SHOULD LIFT BY 16Z AT TAF SITES...BUT COULD
CLING TO THE IMMEDIATE COAST INTO THE AFTERNOON. ABOVE THE MARINE
LAYER AND INLAND...SKIES WILL BE MOSTLY CLEAR AND VIS UNRESTRICTED
THROUGH TONIGHT...EXCEPT FOR A FEW CU/TCU OVER THE MOUNTAINS IN THE
AFTERNOON.
&&
.FIRE WEATHER...LOW RELATIVE HUMIDITIES WILL CONTINUE TODAY WITH
WIDESPREAD RH VALUES OF 10 PERCENT OR LESS IN THE DESERTS AND THE
N/E MTN SLOPES. EXPECT ONLY MINOR RH INCREASES SUNDAY DUE TO 4 TO 8
DEGREES OF COOLING. WINDS WILL GENERALLY BE LIGHT THROUGH SATURDAY
NIGHT...BUT SOME GUSTY WINDS OVER THE MTNS/DESERTS WILL CREATE NEAR
CRITICAL FIRE WEATHER CONDITIONS SUNDAY AS THE ONSHORE PRESSURE
GRADIENTS INCREASE...WITH STRONGEST WINDS LATE AFTERNOON/EVENING.
LOCAL WINDS GREATER THAN 25 MPH AND LOCAL GUSTS OF 35 MPH WILL BE
POSSIBLE ON THE DESERT MTN SLOPES AND INTO THE ADJACENT DESERTS. DUE
TO THE LATE DAY TIMING OF THE WINDS...THE COMBINATION OF 15 PERCENT
RH AND 25 MPH SUSTAINED WINDS IS NOT FORECAST FOR MORE THAN 6 HOURS.
LIGHTER WINDS AND HIGHER RHS ARE EXPECTED MONDAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC/FIRE WEATHER...MOEDE
AVIATION...JAD
000
FXUS66 KMTR 041029
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
300 AM PDT SAT SEP 4 2010
.DISCUSSION...AS OF 2:45 AM PDT SATURDAY...LATEST SATL FOG PRODUCT
AND SURFACE OBSERVATIONS SHOW LOW CLOUDS AND FOG HAVE PUSHED INTO
THE NORTH BAY VALLEYS...INTO SAN FRANCISCO BAY AND SAN PABLO BAY
AND INLAND FROM MONTEREY BAY TO HOLLISTER AND WELL DOWN THE SALINAS
VALLEY. ONSHORE GRADIENTS ARE ABOUT THE SAME AS 24 HRS AGO AT
CLOSE TO 3 MB. MARINE INVERSION RUNNING CLOSE TO 1000 FT THIS AM.
TODAY`S HIGHS SHOULD BE VERY SIMILAR TO YESTERDAYS EXCEPT A FEW
DEGREES COOLER COAST AND COASTAL VALLEYS. NORTH BAY INTERIOR VALLEYS
WILL SEE SOME SLIGHT COOLING TODAY BUT INTERIOR LOCATIONS OF THE EAST
BAY AND SOUTHERN SALINAS VALLEYS MAY SEE A FEW DEGREES OF WARMING.
UPPER TROUGH MOVING INTO THE PACNW APPEARS TO BE LIFTING MORE TO
THE NE THEN MODELS HAD EARLIER PREDICTED. THIS WILL KEEP HEIGHTS
AND TEMPS OVER OUR AREA NEAR STATUS QUO EXCEPT IN SOUTHERN QUARTER
OF THE DISTRICT WHERE 850 TEMPS COOL SLIGHTLY. SO EXPECT LITTLE
TEMPERATURE CHANGE SUNDAY EXCEPT SOUTHERN SECTIONS OF THE SALINAS
VALLEY AND SURROUNDING HILLS. MODELS ARE INDICATING WEAK OFFSHORE
FLOW TO BEGIN AS EARLY AS LATE SUNDAY WITH LOW CLOUDS PUSHED OFF THE
COAST AND WILL REMAIN WELL AWAY FROM THE COAST MONDAY.
FAIR SKIES SUNDAY NIGHT INTO LABOR DAY WITH THE WEAK OFFSHORE
FLOW KEEPING SKIES CLEAR ALL DAY MONDAY WITH TEMPERATURES WARMING AT
THE COAST AND COASTAL VALLEYS. MAY SEE SOME BREEZY CONDITIONS IN THE
NORTH BAY HILLS OVERNIGHT SUNDAY INTO MONDAY MORNING. THESE WINDS
WILL HELP WARM COASTAL AREAS WHERE NEAR 80 DEGREES IS POSSIBLE IN
DOWNTOWN SAN FRANCISCO LABOR DAY WITH 80S AND 90S THE RULE MOST OTHER
LOCATIONS. THIS WARM-UP WILL BE VERY BRIEF SO ENJOY THE LABOR HOLIDAY
WARMTH AND SUNNY SKIES.
EXTENDED...TUESDAY WILL SEE A DRAMATIC DROP IN TEMPERATURES AS A
VIGOROUS UPPER TROUGH DIGS SOUTH FROM CANADA DOWN THE COAST OF WA
AND OR. THIS TROUGH WILL RAPIDLY DEEPEN THE MARINE LAYER AND ALLOW
LOW CLOUDS AND FOG TO QUICKLY FORM OVER NIGHT MONDAY MOVING WELL
INLAND BY TUESDAY MORNING. FIFTEEN TO 25 DEGREE TEMPERATURE DROPS
WILL BE THE NORM FOR TUE FROM WHAT WILL OCCUR LABOR DAY. THESE
WILL BE 10 TO 15 DEGREES BELOW NORMAL FOR EARLY SEPTEMBER. THESE
COOL TEMPERATURES WILL CONTINUE WED INTO THURSDAY AS THE UPPER
TROUGH WILL BE SLOW TO MOVE EAST UNTIL THURSDAY. A SLOW WARMING
TREND WILL BEGIN THURSDAY MAINLY INTERIOR VALLEYS AS A BAGGY WEAK
TROUGH REMAINS OVER THE WEST COAST INTO NEXT WEEKEND. TEMPERATURES
WILL REMAIN BELOW NORMAL THROUGH THE EXTENDED PERIOD WITH NIGHT
AND MORNING COASTAL LOW CLOUDS MOVING WELL INLAND NIGHTS AND
MORNINGS.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...THE EXTENSIVE STRATUS FIELD
ALONG THE COAST AND OFFSHORE HAS BEGUN TO PENETRATE INTO THE
COASTAL VALLEYS AT THIS TIME WITH BASES AS LOW AS 200 FEET AND
TOPS NEAR 1200 FEET. THE LOW CLOUDS WILL CONTINUE TO SPREAD
INTO COASTAL VALLEYS OVERNIGHT. AN UPPER LEVEL TROUGH APPROACHING
CALIFORNIA SHOULD ENHANCE THE MARINE LAYER AND DEEPEN IT
OVERNIGHT.DEEP ENOUGH MOISTURE SUPPLY TO GENERATE SHOWER ACTIVITY. A
MORE LIKELY SCENARIO WILL BE MEASURABLE DRIZZLE NEAR THE COAST AND ON
THE WEST SLOPES OF THE COASTAL RANGES AS A DEEP MARINE LAYER SURGES
INLAND.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...THE EXTENSIVE STRATUS FIELD
ALONG THE COAST AND OFFSHORE HAS BEGUN TO PENETRATE INTO THE
COASTAL VALLEYS AT THIS TIME WITH BASES AS LOW AS 200 FEET AND
TOPS NEAR 1200 FEET. THE LOW CLOUDS WILL CONTINUE TO SPREAD
INTO COASTAL VALLEYS OVERNIGHT. AN UPPER LEVEL TROUGH APPROACHING
CALIFORNIA SHOULD ENHANCE THE MARINE LAYER AND DEEPEN IT OVERNIGHT.
THE LOW CLOUDS SHOULD ERODE TO THE COAST BY 19Z.
.VICINITY OF KSFO...VFR THRU 09Z...THEN IFR CIGS THRU 18Z. GUSTY
NORTHWEST WINDS WILL ONCE AGAIN DEVELOP AROUND 21Z.
.KSFO BRIDGE APPROACH...VFR THRU 08Z...THEN IFR CIGS SPREADING OVER
THE APPROACH BY 10Z. VFR RETURNING BY 18Z.
.MRY BAY AREA TERMINALS...LIFR CIGS THRU 17Z AND LOCAL IFR
VISIBILITIES THRU 14Z. LOW CLOUDS AND FOG CLEARING TO THE COAST
BETWEEN 18Z AND 19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.AFTERNOON...SCA...NORTHERN OUTER WATERS AND SAN
FRANCISCO BAY.
&&
$$
PUBLIC FORECAST: REYNOLDS
AVIATION/MARINE: EVANS
000
FXUS66 KMTR 041028
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
300 AM PDT FRI SEP 4 2010
.DISCUSSION...AS OF 2:45 AM PDT SATURDAY...LATEST SATL FOG PRODUCT
AND SURFACE OBSERVATIONS SHOW LOW CLOUDS AND FOG HAVE PUSHED INTO
THE NORTH BAY VALLEYS...INTO SAN FRANCISCO BAY AND SAN PABLO BAY
AND INLAND FROM MONTEREY BAY TO HOLLISTER AND WELL DOWN THE SALINAS
VALLEY. ONSHORE GRADIENTS ARE ABOUT THE SAME AS 24 HRS AGO AT
CLOSE TO 3 MB. MARINE INVERSION RUNNING CLOSE TO 1000 FT THIS AM.
TODAY`S HIGHS SHOULD BE VERY SIMILAR TO YESTERDAYS EXCEPT A FEW
DEGREES COOLER COAST AND COASTAL VALLEYS. NORTH BAY INTERIOR VALLEYS
WILL SEE SOME SLIGHT COOLING TODAY BUT INTERIOR LOCATIONS OF THE EAST
BAY AND SOUTHERN SALINAS VALLEYS MAY SEE A FEW DEGREES OF WARMING.
UPPER TROUGH MOVING INTO THE PACNW APPEARS TO BE LIFTING MORE TO
THE NE THEN MODELS HAD EARLIER PREDICTED. THIS WILL KEEP HEIGHTS
AND TEMPS OVER OUR AREA NEAR STATUS QUO EXCEPT IN SOUTHERN QUARTER
OF THE DISTRICT WHERE 850 TEMPS COOL SLIGHTLY. SO EXPECT LITTLE
TEMPERATURE CHANGE SUNDAY EXCEPT SOUTHERN SECTIONS OF THE SALINAS
VALLEY AND SURROUNDING HILLS. MODELS ARE INDICATING WEAK OFFSHORE
FLOW TO BEGIN AS EARLY AS LATE SUNDAY WITH LOW CLOUDS PUSHED OFF THE
COAST AND WILL REMAIN WELL AWAY FROM THE COAST MONDAY.
FAIR SKIES SUNDAY NIGHT INTO LABOR DAY WITH THE WEAK OFFSHORE
FLOW KEEPING SKIES CLEAR ALL DAY MONDAY WITH TEMPERATURES WARMING AT
THE COAST AND COASTAL VALLEYS. MAY SEE SOME BREEZY CONDITIONS IN THE
NORTH BAY HILLS OVERNIGHT SUNDAY INTO MONDAY MORNING. THESE WINDS
WILL HELP WARM COASTAL AREAS WHERE NEAR 80 DEGREES IS POSSIBLE IN
DOWNTOWN SAN FRANCISCO LABOR DAY WITH 80S AND 90S THE RULE MOST OTHER
LOCATIONS. THIS WARM-UP WILL BE VERY BRIEF SO ENJOY THE LABOR HOLIDAY
WARMTH AND SUNNY SKIES.
EXTENDED...TUESDAY WILL SEE A DRAMATIC DROP IN TEMPERATURES AS A
VIGOROUS UPPER TROUGH DIGS SOUTH FROM CANADA DOWN THE COAST OF WA
AND OR. THIS TROUGH WILL RAPIDLY DEEPEN THE MARINE LAYER AND ALLOW
LOW CLOUDS AND FOG TO QUICKLY FORM OVER NIGHT MONDAY MOVING WELL
INLAND BY TUESDAY MORNING. FIFTEEN TO 25 DEGREE TEMPERATURE DROPS
WILL BE THE NORM FOR TUE FROM WHAT WILL OCCUR LABOR DAY. THESE
WILL BE 10 TO 15 DEGREES BELOW NORMAL FOR EARLY SEPTEMBER. THESE
COOL TEMPERATURES WILL CONTINUE WED INTO THURSDAY AS THE UPPER
TROUGH WILL BE SLOW TO MOVE EAST UNTIL THURSDAY. A SLOW WARMING
TREND WILL BEGIN THURSDAY MAINLY INTERIOR VALLEYS AS A BAGGY WEAK
TROUGH REMAINS OVER THE WEST COAST INTO NEXT WEEKEND. TEMPERATURES
WILL REMAIN BELOW NORMAL THROUGH THE EXTENDED PERIOD WITH NIGHT
AND MORNING COASTAL LOW CLOUDS MOVING WELL INLAND NIGHTS AND
MORNINGS.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...THE EXTENSIVE STRATUS FIELD
ALONG THE COAST AND OFFSHORE HAS BEGUN TO PENETRATE INTO THE
COASTAL VALLEYS AT THIS TIME WITH BASES AS LOW AS 200 FEET AND
TOPS NEAR 1200 FEET. THE LOW CLOUDS WILL CONTINUE TO SPREAD
INTO COASTAL VALLEYS OVERNIGHT. AN UPPER LEVEL TROUGH APPROACHING
CALIFORNIA SHOULD ENHANCE THE MARINE LAYER AND DEEPEN IT
OVERNIGHT.DEEP ENOUGH MOISTURE SUPPLY TO GENERATE SHOWER ACTIVITY. A
MORE LIKELY SCENARIO WILL BE MEASURABLE DRIZZLE NEAR THE COAST AND ON
THE WEST SLOPES OF THE COASTAL RANGES AS A DEEP MARINE LAYER SURGES
INLAND.
&&
.AVIATION...AS OF 10:30 PM PDT FRIDAY...THE EXTENSIVE STRATUS FIELD
ALONG THE COAST AND OFFSHORE HAS BEGUN TO PENETRATE INTO THE
COASTAL VALLEYS AT THIS TIME WITH BASES AS LOW AS 200 FEET AND
TOPS NEAR 1200 FEET. THE LOW CLOUDS WILL CONTINUE TO SPREAD
INTO COASTAL VALLEYS OVERNIGHT. AN UPPER LEVEL TROUGH APPROACHING
CALIFORNIA SHOULD ENHANCE THE MARINE LAYER AND DEEPEN IT OVERNIGHT.
THE LOW CLOUDS SHOULD ERODE TO THE COAST BY 19Z.
.VICINITY OF KSFO...VFR THRU 09Z...THEN IFR CIGS THRU 18Z. GUSTY
NORTHWEST WINDS WILL ONCE AGAIN DEVELOP AROUND 21Z.
.KSFO BRIDGE APPROACH...VFR THRU 08Z...THEN IFR CIGS SPREADING OVER
THE APPROACH BY 10Z. VFR RETURNING BY 18Z.
.MRY BAY AREA TERMINALS...LIFR CIGS THRU 17Z AND LOCAL IFR
VISIBILITIES THRU 14Z. LOW CLOUDS AND FOG CLEARING TO THE COAST
BETWEEN 18Z AND 19Z.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.AFTERNOON...SCA...NORTHERN OUTER WATERS AND SAN
FRANCISCO BAY.
&&
$$
PUBLIC FORECAST: REYNOLDS
AVIATION/MARINE: EVANS
000
FXUS66 KSTO 041022
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
330 AM PDT SAT SEP 4 2010
.DISCUSSION...
STRONG HIGH PRESSURE OVER NORCAL WILL CONTINUE TO GRADUALLY WEAKEN
THE NEXT DAY OR SO AS THE SHORT-WAVE TROUGH NOW OVER BC DROPS
SOUTHEASTWARD INTO THE NORTHERN ROCKIES ON SUNDAY. THE MARINE LAYER
HAS DEEPENED A BIT ALONG THE COAST IN RESPONSE TO WEAKER SUBSIDENCE
AND IS NOW A LITTLE OVER 1000 FT DEEP AT FT. ORD. THE COMBINATION OF
A LITTLE MORE ONSHORE FLOW AND SLIGHT AIRMASS COOLING WILL RESULT IN
A BIT COOLER TEMPERATURES ACROSS THE REGION TODAY. MORE SIGNIFICANT
AIRMASS COOLING WILL TAKE PLACE ACROSS MUCH OF THE REGION ON SUNDAY
AS THE TROUGH MOVES BY TO THE NORTH AND EAST...BUT THE MOST
SIGNIFICANT COOLING WILL TAKE PLACE OVER THE NORTHERN PORTION OF THE
FORECAST AREA AS NORTHERLY FLOW DEVELOPS DOWN THE SACRAMENTO VALLEY
IN THE AFTERNOON OFFSETTING THE AIRMASS COOLING BY CUTTING OFF THE
DELTA BREEZE. APPEARS THE STRONGEST NORTHEAST SURFACE GRADIENTS WILL
OCCUR SUNDAY NIGHT AND EARLY MONDAY WITH LOCALLY BREEZY CONDITIONS
EXPECTED ACROSS THE REGION ALONG WITH MILDER OVERNIGHT LOWS.
PATTERN BECOMES MORE INTERESTING AGAIN BY THE MIDDLE OF NEXT WEEK AS
MODELS CONTINUE TO ADVERTISE ANOTHER SYSTEM WEDNESDAY...SIMILAR IN
STRENGTH TO THE ONE THAT BROUGHT THE COOLER WEATHER AND SHOWERS LAST
WEEK. HAVE CONTINUED TO HIGHLIGHT THE CHANCE OF SHOWERS ACROSS THE
NORTH AND OVER THE MOUNTAINS ALONG WITH MUCH COOLER TEMPERATURES FOR
WEDNESDAY INTO THURSDAY.
&&
.AVIATION...
VFR CONDS WITH CLEAR SKIES EXPECTED TO CONT OVER THE NXT 24 HRS. SW
WIND GUSTS TO 25 KT NEAR THE CARQUINEZ STRAIT TDA AND TNGT WITH LCL
ST OVER THE WRN DELTA. LCL GUSTS TO 30 KT OVER NRN SIERRA RIDGES
THIS AFTN AND EVENING. GENERALLY LGT WINDS ELSW.
&&
.STO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
000
FXUS65 KREV 040845
AFDREV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
145 AM PDT SAT SEP 4 2010
.SHORT TERM...
ONLY MINOR TWEAKS MADE TO THE SHORT TERM AS THE FORECAST CONTINUES
TO BE ON TRACK. UPPER LEVEL TROUGH BEGINNING TO MOVE INTO BRITISH
COLUMBIA EARLY THIS MORNING WILL PUNCH DOWN THE RIDGE...LOWERING
HEIGHTS ACROSS THE REGION. THIS WILL BRING BREEZY CONDITIONS
ACROSS THE SIERRA AND WESTERN NEVADA TODAY INTO SUNDAY. A DRY COLD
FRONT ASSOCIATED WITH THE TROUGH WILL PUSH THROUGH THE CWA LATE
SATURDAY NIGHT INTO SUNDAY DROPPING HIGH TEMPERATURES 8 TO 15
DEGREES NORTH OF HIGHWAY 50 AND ABOUT 5 TO 8 DEGREES ELSEWHERE.
RAISED HIGH TEMPERATURES SUNDAY BY A FEW DEGREES SOUTH OF HIGHWAY
50 AND EAST OF PYRAMID LAKE WHICH SHOULD REALIZE MORE MIXING AND
WARMING AHEAD OF THE COLD FRONT.
A DRY AIR MASS MOVES INTO THE REGION SUNDAY NIGHT INTO MONDAY WITH
WINDS DROPPING OFF EVERYWHERE OTHER THAN N-S AND NW-NE ORIENTED
VALLEYS. THIS WILL MAXIMIZE RADIATIONAL COOLING WITH A HARD FREEZE
LIKELY THROUGH MANY SIERRA VALLEYS AND FROST POSSIBLE THROUGH
OUTLYING WESTERN NEVADA VALLEYS.
NORTHERLY FLOW BEHIND THE TROUGH ALONG WITH THE COOL START TO THE
DAY WILL KEEP TEMPERATURES LIMITED ON MONDAY WITH HIGHS A FEW
DEGREES BELOW NORMAL. FLOW BECOMES MORE ZONAL INTO TUESDAY
AHEAD OF THE NEXT TROUGH WHICH WILL BE THE MAIN WEATHER STORY IN
THE LONG TERM. DF
.LONG TERM...TUESDAY THROUGH FRIDAY...
UPPER TROUGH STILL FORECAST TO DIG SOUTHWARD ALONG THE WEST COAST
TUE AND THEN MOVE ACROSS THE REGION WED-THU. LATEST MEDIUM RANGE
MODELS CONTINUE TO AGREE WELL WITH THIS SCENARIO. THE SLIGHTLY
SLOWER ECMWF WILL BE FOLLOWED AS THESE HIGHLY AMPLIFIED DIGGING
SYSTEMS TEND TO PROGRESS SLOWER. SO WARMED TEMPERATURES A BIT FOR
WED AND COOLED THEM A BIT THU TO REFLECT THIS TREND. OVERALL THE MOS
GUIDANCE CONTINUES TO HANDLE TEMPERATURES POORLY AND WILL BE
UNDERCUT SIGNIFICANTLY. MAINTAINED A THREAT FOR SHOWERS ESPECIALLY
WED-THU BUT INTRODUCED A SLIGHT CHANCE OF THUNDER ACROSS PARTS OF
WESTERN NV FOR WED AFTERNOON AND EVENING. BOTH THE OPERATIONAL RUNS
OF THE GFS/ECMWF SHOW MID LEVEL LIFT ASSOCIATED WITH UPPER LEVEL PV
LOBE/JET MAXIMA AND ELEVATED INSTABILITY (MUCAPE 50-100 J/KG) ALONG
LOW LEVEL CONVERGENCE FIELD AHEAD OF TROUGH ACROSS THE BASIN AND
RANGE WITH THE ECMWF FARTHEST WEST WITH FEATURE. HOHMANN
&&
.AVIATION...
VFR. TROF APPROACHING PACNW TODAY WILL CONTINUE TO BRING A GENERAL
WEST FLOW AT RIDGE LEVEL WHERE GUSTS WILL APPROACH 45KT. MIXING OF
UPPER LEVEL WINDS SHOULD ENHANCE ZEPHYR ALONG THE IMMEDIATE LEE OF
THE SIERRA WITH OCCASIONAL GUSTS 25-30KT AT KRNO AND 20-25KT FOR THE
SIERRA TAF SITES. HOHMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
HTTP://WEATHER.GOV/RENO
US Dept of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
1325 East West Highway
Silver Spring, MD 20910
Page Author:
NWS Internet Services Team
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities
|
