Marine Weather Statement 21, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
320 PM PST WED NOV 26 2008

UPDATED AVIATION DISCUSSION

.SHORT TERM (TONIGHT THROUGH SATURDAY)...12Z MODELS ARE IN PRETTY
GOOD SYNOPTIC AGREEMENT THROUGH THE PERIOD. THE UPPER LOW CURRENTLY
SOUTHWEST OF POINT CONCEPTION WILL CONTINUE TO MOVE EASTWARD TONIGHT
AND THURSDAY...FINALLY MOVING EAST OF THE AREA BY THURSDAY AFTERNOON.
FOR THURSDAY NIGHT THROUGH SATURDAY...MODELS BUILD A UPPER RIDGE JUST
OFF THE CALIFORNIA COAST. NEAR THE SURFACE...ONSHORE FLOW WILL
CONTINUE THROUGH THANKSGIVING...THEN GRADUALLY TURN OFFSHORE FRIDAY
AND SATURDAY.

FORECAST WISE...WITH THE UPPER LOW MOVING EAST ACROSS THE AREA
TONIGHT...SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO BE A
THREAT. IN FACT...BOTH MODELS INDICATE SOME SLIGHTLY NEGATIVE LIFTED
INDICES ACROSS VTU/LAX COUNTIES TONIGHT. SHOWERS WILL BE LIKELY MOST
AREAS OVERNIGHT...WITH THE SLIGHT CHANCE OF THUNDERSTORMS. BY LATE
THURSDAY MORNING...THE SHOWER THREAT SHOULD BE LIMITED TO THE VTU/LAX
MOUNTAINS WITH PARTLY CLOUDY SKIES ACROSS THE ENTIRE AREA. WITH THE
CONTINUED SHOWER THREAT...WILL KEEP THE FLASH FLOOD WATCH FOR BURN
AREAS IN EFFECT THROUGH THIS EVENING. DEPENDING HOW THINGS DEVELOP...
THE WATCH MAY HAVE TO BE EXTENDED INTO THURSDAY MORNING. HIGHS ON
THURSDAY WILL REMAIN WELL BELOW NORMAL FOR ALL AREAS.

FOR THURSDAY NIGHT THROUGH SATURDAY...DRY CONDITIONS WITH A WARMING
TREND CAN BE EXPECTED AS THE UPPER-LEVEL RIDGE DEVELOPS AND THE
OFFSHORE FLOW INCREASES. AT THIS TIME...THE UPPER SUPPORT FOR THE
OFFSHORE WINDS IS ONLY MODERATE AT BEST. THEREFORE...WILL EXPECT
WEAK NORTH TO NORTHEAST WINDS THROUGH/BELOW PASSES AND CANYONS THAT
SHOULD REMAIN BELOW ADVISORY LEVELS.

.LONG TERM (SUNDAY THROUGH WEDNESDAY)...OVERALL...NOTHING TOO
DRAMATIC IN THE EXTENDED FORECAST. FOR SUNDAY/MONDAY...UPPER-LEVEL
RIDGE WILL MOVE OVER CALIFORNIA WITH CONTINUED OFFSHORE FLOW. AT
THIS TIME...THE UPPER-LEVEL SUPPORT FOR THE OFFSHORE WINDS WILL PEAK
ON SUNDAY. SO...THERE MAY BE ADVISORY LEVEL WINDS ACROSS THE
MOUNTAIN AND FOOTHILL AREAS. WITH THE RIDGE OVERHEAD AND STRONGER
OFFSHORE FLOW TEMPS SHOULD PEAK ON SUNDAY/MONDAY. AT THIS
TIME...WILL GO WITH TEMPS IN THE 70S TO LOWER 80S WEST OF THE
MOUNTAINS WHICH IS A FEW DEGREES ABOVE CURRENT MEX MOS NUMBERS.

FOR TUESDAY/WEDNESDAY...THE UPPER-LEVEL RIDGE BREAKS DOWN AND WEAK
ONSHORE FLOW BEGINS TO DEVELOP. SO...WILL EXPECT CONTINUED CLEAR
SKIES ACROSS THE AREA WITH A FEW DEGREES OF COOLING ACROSS THE AREA.

&&

.AVIATION...26/2320Z.
MOST AIRPORTS WILL SEE MVFR/VFR CONDITIONS THROUGH TONIGHT...WITH
BKN-OVC CIGS AND -SHRA. SHOWERS WILL BE PERIODIC AND WILL BECOME
FOCUSED OVER LA/VTU/ AND SRN SBA COUNTIES. THE THREAT OF TSRA
REMAINS THROUGH AT LEAST THIS EVENING...BUT MOSTLY TO THE SOUTH. THE
HEAVIER SHOWERS AND/OR THUNDERSTORMS MAY PRODUCE SOME IFR CONDITIONS
WITH CIGS NEAR 015 AND VIS UNDER 3SM...BUT WILL BE BRIEF. THINGS
SHOULD IMPROVE THU MORNING...BUT LOW CONFIDENCE ON EXACT TIMING.

KLAX...VFR CATS WILL CONTINUE THROUGH MUCH OF TONIGHT...BUT WITH
CIGS ABOVE 040 AND VIS NEAR 6SM. RAIN WILL ALSO CONTINUE AS PERIODIC
SHOWERS WITH THUNDERSTORMS POSSIBLE. MVFR CATS ARE EXPECTED UNDER
SHOWERS/THUNDERSTORMS...WITH BRIEF IFR POSSIBLE. WINDS WILL BECOME
EAST OVERNIGHT...BUT NOT EXPECTED TO BE ABOVE 10 KT FOR AN EXTENDED
PERIOD OF TIME.

KBUR...MVFR CATS WILL CONTINUE THROUGH MUCH OF TONIGHT. RAIN WILL
ALSO CONTINUE AS PERIODIC SHOWERS WITH THUNDERSTORMS POSSIBLE. IFR
CATS ARE EXPECTED UNDER HEAVIER SHOWERS/THUNDERSTORMS.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH (SEE LAXFFALOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&

PUBLIC...THOMPSON
AVIATION...KITTELL

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