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000 FXUS66 KLOX 151810 AFDLOX SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 1100 AM PDT MON SEP 15 2008 .SHORT TERM... JUST A QUICK NOTE TO INDICATE THAT THERE WILL BE NO MORNING UPDATE AS THE CURRENT FORECAST PACKAGE IS IN GOOD SHAPE. IN FACT...I DO NOT FORESEE ANY CHANGES TO THE FORECAST FOR THE NEXT FEW DAYS. THE WEATHER HEADLINE FOR THE NEXT COUPLE OF DAYS WILL BE THE HOT DAYTIME TEMPERATURES AS A RIDGE TO OUR EAST WILL CONSPIRE WITH NEUTRAL SURFACE PRESSURE GRADIENTS TO INCREASE TEMPERATURES CONSIDERABLY TODAY AND TUESDAY. THE RESULTANT SOUTHERLY FLOW ALOFT WILL IMPORT SOME MID LEVEL MOISTURE BY TUESDAY AFTERNOON. THE MOISTURE WILL COMBINE WITH MARGINAL INSTABILITY AND THE HEAT TO GENERATE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE MOUNTAINS AND DESERTS TUESDAY AFTERNOON. ONE SLIGHT CHANGE TO THE FORECAST MAY CONCERN THE MARINE CLOUDS. THE LATEST SATELLITE PICTURES INDICATE A POSSIBILITY OF PATCHY LOW CLOUDS MOVING INTO THE COAST SOUTH OF POINT CONCEPTION TONIGHT. THIS QUESTION WILL BE ANSWERED WITH A LAST MINUTE DECISION BASED ON THE LATEST SATELLITE TRENDS. FINALLY...GUSTY NORTHWEST WINDS WILL BE A POSSIBILITY ACROSS SANTA BARBARA COUNTY PASSES AND CANYONS FOR THE NEXT COUPLE OF DAYS. FOR TUESDAY NIGHT AND WEDNESDAY...THE FLOW ALOFT WILL SHIFT TO THE SOUTHWEST AND COMBINED WITH SLIGHT COOLING AND DECREASED INSTABILITY ACROSS THE REGION...ONLY AFTERNOON CLOUDS WILL BE MENTIONED ACROSS THE MOUNTAINS AND DESERTS FOR WEDNESDAY AFTERNOON. MEANWHILE...A SLIGHT INCREASE IN ONSHORE FLOW MAY BE ENOUGH TO INSPIRE AN INCREASE IN MARINE CLOUD COVERAGE FOR COASTAL SECTIONS SOUTH OF POINT CONCEPTION. .FIRE WX... FIRE WEATHER WATCH FOR SAN LUIS OBISPO COUNTY MOUNTAINS HAS BEEN CANCELLED THIS MORNING. THE RED FLAG WARNING FOR OTHER MOUNTAIN FIRE WEATHER ZONES REMAINS IN EFFECT UNTIL 7 PM THIS EVENING. .LONG TERM...FROM PREVIOUS DISCUSSION...GFS AND EC CAN ONLY AGREES THROUGH THURSDAY EVENING AND THEN DIVERGE AS THEY ATTEMPT TO HANDLE A SMALL LOW MOVING INTO SOUTHERN OREGON. THE GFS IS AS USUAL CUT OFF HAPPY AND KEEPS THE LOW TIGHTLY BUNCHED AND MOVES IT DOWN THE CA COAST WHILE THE EC OPENS IT UP AND MOVES IT INTO IDAHO. GFS ENSEMBLES INDICATE THAT THE GFS SOLN IS QUESTIONABLE AND LEANED TO THE EC FOR LONG RANGE GUIDANCE. THAT SAID LOOK FOR TROFING PATTER THROUGH FRIDAY WHICH SHOULD GIVE US NIGHT AND MORNING CLOUDS OVER THE COASTS AND MOST OF THE VLYS. HIGHER HGTS SHOULD BUILD IN FOR THE WEEKEND AND SMOOSH THE MARINE LAYER WHILE RISING HGTS WILL WARM THINGS UP. && .AVIATION...15/1745Z MARINE LAYER BETWEEN 008-012...WITH A FAIRLY SCATTERED STRATUS PATTERN. OTHER THAN CIGS AT KSMX AND SOME HZ AT KOXR KLAX AND KLGB...ALL AIRPORTS ARE VFR. VFR CATS SHOULD PREVAIL EVERYWHERE AFTER 19Z. WESTERLY WINDS WILL BE STRONGER THAN NORMAL ALONG THE COAST...WITH SOME GUSTS ABOVE 15 KT EXPECTED AT KSBA KOXR AND KLAX. MODERATE CONFIDENCE OF SIMILAR STRATUS AT KSMX AND KSBP. LOW CONFIDENCE IN WHAT STRATUS WILL DO AT KOXR KLAX AND KOXR...BUT BEST CHANCE OF STAYING CIG FREE. KLAX...HIGH CONFIDENCE IN VFR FROM 20Z THROUGH EARLY THIS EVENING. STRONGER THAN NORMAL WEST WIND EXPECTED THIS AFTERNOON. LOW CONFIDENCE IN RETURN OF STRATUS TONIGHT...BUT MODERATE CONFIDENCE IN SOME MVFR HAZE AFTER 12Z. KBUR...HIGH CONFIDENCE IN VFR THROUGH TONIGHT. && .LOX WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING (SEE LAXRFWLOX). GALE WARNING (SEE LAXMWWLOX). SMALL CRAFT ADVISORY (SEE LAXMWWLOX). && $$ PUBLIC...SWEET/RORKE AVIATION...HALL WWW.WEATHER.GOV/LOSANGELES