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000
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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