FXUS66 KLOX 011110
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
300 AM PST TUE DEC 1 2009
.SYNOPSIS...
THE MARINE LAYER WILL SLOWLY REDEVELOP TODAY THROUGH THURSDAY
CREATING A COOLING TREND. OFFSHORE FLOW WILL CREATE CLEAR SKIES AND
WARMER WEATHER ON FRIDAY. CLOUDS WILL SLOWLY INCREASE OVER THE
WEEKEND LEADING TO A CHANCE OF RAIN EARLY NEXT WEEK.
&&
.SHORT TERM (TODAY-FRI)...
WEAK RIDGE WITH WEAK OFFSHORE FLOW OVER THE AREA TODAY. A LITTLE
RETURN OF THE MARINE LAYER ACROSS THE CENTRAL COAST WITH SOME DENSE
FOG AS WELL. SOME HIGH LEVEL CLOUDS WILL ALSO DRIFT ACROSS THE AREA
WHICH WILL SHIFT THE FORECAST FROM SUNNY TO MOSTLY SUNNY. OFFSHORE
FLOW IS WEAKER THAN YDY AND MAX TEMPS WILL DROP A FEW DEGREES.
TONIGHT OFFSHORE FLOW FLIPS TO ONSHORE AS RIDGE IS PUSHED BACKWARDS
BY A HUMONGOUS CONUS SPANNING UPPER LOW WHICH ALSO TURNS THE UPPER
FLOW FROM ANTICYCLONIC TO CYCLONIC BOTH THESE ITEMS SHOULD COMBINE
TO SPAWN A DECENT MARINE LAYER ACROSS THE COASTS AND LOCALLY INTO
THE LOWEST VALLEYS.
BIGGEST FORECAST QUESTION FOR WEDNESDAY IS WHETHER OR NOT TO WORD
THE FORECAST AS MOSTLY SUNNY OR PARTLY CLOUDY AS IT LOOKS LIKE THERE
COULD BE QUITE A BIT OF MID AND HIGH LEVEL CLOUDS DRIFTING OVERHEAD.
TEMPS WILL CONTINUE TO COOL WITH ONSHORE FLOW AND HGTS FALLING TO
567 DM.
MORE MARINE LAYER FILLING MOST OF THE VALLEYS WED NIGHT DUE TO
BETTER ONSHORE FLOW. THURSDAY WILL DAWN WITH LOW CLOUDS COVERING
MOST OF THE COASTS AND VLYS. THESE CLOUDS WILL BURN OFF AND THE REST
OF THE DAY WILL BE MOSTLY SUNNY. HGTS RISE SOME AS THE RIDGE TRIES
TO REESTABLISH ITSELF OVER THE WEST AND THIS SHOULD BE GOOD FOR A
COUPLE OF DEGREES OF WARMING.
AS THE RIDGE BUILDS IN FROM THE WEST A LARGE SURFACE HIGH DROPS INTO
NEVADA CREATING A BURST OF OFFSHORE FLOW. DO NOT SEE ENOUGH COLD AIR
ADVECTION OR UPPER SUPPORT FOR ADVISORY LEVEL WINDS BUT THERE WILL
BE TYPICAL 15 TO 25 MPH CANYONS WINDS. THE OFFSHORE FLOW SHOULD
CLEAR THE MARINE LAYER AND WILL WARM THINGS ENOUGH TO MAKE FRIDAY
THE WARMEST DAY OF THE NEXT SEVEN.
.LONG TERM (SAT-MON)...
THE EC AND GFS DO AGREE THAT SATURDAY WILL BE COOLER AS THE SURFACE
HIGH MOVES EASTWARD AND THE RIDGE IS KNOCKED DOWN BY A PAC NW STORM.
TEMPS WILL DROP FROM FRIDAYS WARM VALUES BUT IT WILL STILL BE NICE
DAY.
EC AND GFS STOP AGREEING SUNDAY. GFS ENSEMBLES SCATTER IN ALL
DIRECTIONS AS WELL. THESE TWO THINGS ADD UP TO A VERY LOW CONFIDENCE
FORECAST FOR THE END OF THE PERIOD. GFS CONTINUES TO BUILD A LARGE
LOW INTO NEVADA FORCING THE JET AND THE STORM TRACK DOWN INTO MEXICO
AND KEEPING THINGS FAIRLY DRY. THE EC AND GEM CONTINUE WITH THE MORE
AGGRESSIVE WEST FLOW RAIN SOLUTION BRINGING RAIN ON SUNDAY AND GOOD
RAIN ON MONDAY...TUESDAY...WEDNESDAY AND ESPECIALLY THURSDAY. WITH
SO MUCH UNCERTAINTY WITH THE FORECAST KEPT THE CLOUDY SKIES COOL
TEMPS AND SLGT CHC TO CHC POP WORDING IN THE LONG TERM FCST BUT IT
REALLY LOOKS LIKE WE ARE GOING TO GET RAIN SOMETIME NEXT WEEK ITS
JUST A MATTER OF WHEN.
&&
.AVIATION...
01/1200Z
MARINE LAYER STARTING TO MAKE A COMEBACK ALONG THE COAST...WITH
LIFR CONDS AT KSBP AND KSMX. EXPECT THESE LIFR CONDS TO DISSIPATE
AROUND 18Z THIS MORNING...BEFORE RETURNING EARLY THIS EVENING.
FOR AREAS SOUTH OF PT CONCEPTION...THE MARINE LAYER SHOULD ALSO
MAKE A RETURN AS ONSHORE ESTABLISHED. EXPECT MVFR/IFR CONDS FOR
COASTAL TAFS...EXCEPT FOR KSBA THRU 12Z.
KLAX...HIGH CONFIDENCE IN VFR CONDS THRU THIS EVENING. EXPECT
IFR CONDS TO RETURN TONIGHT. CURRENT TIMING (07Z) OF STRATUS
RETURN MAY BE OFF BY A COUPLE OF HOURS DEPENDING ON HOW QUICKLY
THINGS DEVELOP. WITH HIGH CLOUDS...THERE IS A SLIGHT CHANCE THAT
STRATUS WILL NOT FORM.
KBUR...HIGH CONFIDENCE IN VFR CONDS THRU 12Z TUE.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...RORKE
AVIATION...THOMPSON
SYNOPSIS...ASR
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