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 WWW.WEATHER.GOV/LOSANGELES