810 
FXUS66 KLOX 162338 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED 
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
440 PM PDT THU MAY 16 2013

UPDATED AVIATION DISCUSSION

.SYNOPSIS...

THE ONSHORE FLOW WILL BRING OVERNIGHT LOW CLOUDS...FOG...WITH 
DRIZZLE OR SPRINKLES INTO FRIDAY MORNING. AFTERNOON TEMPERATURES 
WILL BE BELOW NORMAL THROUGH SATURDAY WITH BREEZY WINDS...ESPECIALLY 
IN THE MOUNTAINS AND DESERTS. A HIGH WILL MOVE IN SUNDAY TO RAISE 
TEMPERATURES TO ABOVE NORMAL AND REDUCE THE MARINE LAYER THROUGH 
MONDAY. A LOW SYSTEM WILL ARRIVE ON TUESDAY TO DEEPEN THE MARINE 
LAYER...INCREASE WINDS...AND LOWER TEMPERATURES THROUGH THURSDAY.

&&

.SHORT TERM (TODAY-SUN)...A TROF MOVING THROUGH THE AREA TODAY IS 
BRINGING A SWATH OF MOSTLY HIGH CLOUDS WITH IT, RESULTING IN EITHER 
PARTLY OR MOSTLY CLOUDY SKIES. THE MARINE LYR, WHICH EARLIER 
DEEPENED TO 3000 FT, HAS MOSTLY BURNED OFF UNDER A WEAKENING 
INVERSION BUT MODERATE ONSHORE FLOW. THE TROF'S BIGGEST IMPACTS WILL 
BE TO INCREASE WEST TO NORTHWEST WINDS ACROSS THE AREA OVER THE NEXT 
24-36 HOURS AND MAINTAINING SLIGHTLY BELOW NORMAL DAYTIME 
TEMPERATURES. MARINE LYR DEVELOPMENT TONIGHT IS ANYTHING BUT A SURE 
THING AS THE WEAK INVERSION AND HIGH CLOUD COVERAGE WILL LIKELY KEEP 
LOW CLOUD COVERAGE PATCHY AT BEST. LEFT IN DRIZZLE AS THERE'S ENOUGH 
ONSHORE PUSH AND COOLING ALOFT TO GENERATE LIFT IN THE LOWER LVLS, 
MAINLY FOR LA COUNTY, BUT LOW CLOUD COVERAGE MAY BE TOO MINIMAL.

ANOTHER COOLER THAN NORMAL DAY FRIDAY WITH BREEZY CONDITIONS FOR THE 
COAST, MOUNTAINS, AND ANTELOPE VALLEY. WINDS EXPECTED TO REMAIN 
BELOW ADVISORY LEVELS IN MOST AREAS EXCEPT POSSIBLY THE AV. THE HIGH 
CLOUDS FROM THE TROF EXPECTED TO PASS THROUGH BY MORNING SO EITHER 
MOSTLY SUNNY OR PARTLY CLOUDY MOST AREAS BY AFTERNOON.

A WARMING TREND EXPECTED TO BEGIN SATURDAY, MAINLY FOR INLAND AREAS. 
STILL A FAIRLY WEAK INVERSION FOR SOUTHERN AREAS SO NOT A REAL SOLID 
MARINE LYR EXPECTED. RIDGE STARTS BUILDING OVER THE AREA LATE 
SATURDAY INTO SUNDAY FOR MORE SIGNIFICANT WARMING FOR INLAND AREAS 
AND LESS SO FOR THE COAST AS ONSHORE FLOW PERSISTS. THE BUILDING OF 
THE RIDGE WITH TROFFING TO OUR EAST WILL PUT THE SQUEEZE ON THE 
WINDS SATURDAY NIGHT INTO EARLY SUNDAY AND WE COULD SEE SOME 
ADVISORY LEVEL NORTHWEST WINDS OVER THE GRAPEVINE AND SRN SBA COUNTY 
DURING THAT TIME. 

.LONG TERM (MON-THU)...WARMEST DAY OF THE PERIOD EXPECTED TO BE 
MONDAY UNDER WEAK OFFSHORE FLOW. DOESN'T LOOK QUITE AS WARM AS IT 
DID A COUPLE DAYS AGO BUT STILL 90S IN THE VALLEYS AND 70S TO LOWER 
80S FOR COASTAL AREAS. JUST A BRIEF WARMUP THOUGH AS THE NEXT TROF 
BRINGS COOLER TEMPS AND BREEZY ONSHORE FLOW TO THE AREA THROUGH THE 
REMAINDER OF NEXT WEEK, ESPECIALLY BY THU AND FRI.

&&

.AVIATION...16/2340Z...
FAIRLY LOW CONFIDENCE IN 00Z TAF FORECAST AS IT IS UNCERTAIN EXACTLY
HOW MUCH STRATUS WILL REDEVELOP TONIGHT. THE INVERSION IS QUITE WEAK 
BEHIND THE FRONTAL PASSAGE. AT THIS POINT...WILL CONTINUE THE IDEA 
WITH STRATUS RE-FORMING AND AFFECTING MOST COASTAL AND VALLEY AREAS 
LATE TONIGHT/FRI MORNING...WITH CONDS MAINLY MVFR.


KLAX...LOW TO MODERATE CONFIDENCE IN 00Z TAFS. THERE IS A 30% CHANCE 
THAT CONDS WILL REMAIN VFR THROUGH THE PERIOD.


KBUR...LOW TO MODERATE CONFIDENCE IN 00Z TAFS. THERE IS A 30% CHANCE 
THAT CONDS WILL REMAIN VFR THROUGH THE PERIOD.
&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY (SEE LAXNPWLOX).
GALE WARNING (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

$$

PUBLIC...MW
AVIATION...SMITH
SYNOPSIS...SETO

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