000 FXUS66 KLOX 211631 AFDLOX SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 933 AM PDT FRI OCT 21 2005 .SHORT TERM... MARINE LAYER NEAR 1500 FT DEEP AT LAX AND NEAR NEUTRAL PRESSURE GRADIENTS IS KEEPING THE STRATUS AROUND A LITTLE LONGER THAN EXPECTED THIS MORNING. NORTH OF POINT CONCEPTION THE MARINE LAYER DEPTH IS ONLY AROUND 500 FT AND THIS IS ALLOWING PATCHY DENSE FOG TO LINGER. BY LATE MORNING...THE STRATUS SHOULD BE CLEARING OUT OF THE VALLEYS AND EVENTUALLY BREAK UP OVER THE COASTAL PLAIN...THOUGH POSSIBLY LINGER ALONG THE BEACHES DURING THE AFTERNOON. OTHERWISE...NO CHANGES NEEDED TO THE FORECAST. ...FROM PREVIOUS DISCUSSION... INCREASED ONSHORE FLOW TONIGHT SHOULD PROHIBIT DENSE FOG BUT WILL KEEP MAIRNE LAYER DEEP INTO THE VALLEYS. WEAK RIDGING AND ONSHORE FLOW LOOK TO KEEP THE FORECAST PRETTY MUCH THE THROUGH SUNDAY WITH NIGHT THROUGH MORNING CLOUDS AND SUNNY AFTERNOONS. INLAND MAY BE A LITTLE WARMER THAN INDICATED BU PREVIOUS MDL RUNS AND BUMPED TEMPS UP A FEW DEGREES THERE. .LONG TERM... THE 580DM 500 MB HGT LINE DANCES BETWEEN CYCLONIC FLOW AND ANIT - CYCLONIC FLOW THROUGH THE EXTENDED PERIOD. THIS REALLY SHOULD NOT AFFECT THE WEATHER MUCH WHICH WILL BE DOMINATED BY ONSHORE FLOW AND A MARINE LAYER. THIS SET UP WILL KEEP TEMPS A LITTLE BELOW NORMS COASTS AND VLYS AND ABOUT NORMAL INLAND. OF POSSIBLE EXCITEMENT VALUE...CURRENT GFS DRAGS A RELITIVELY MOIST FRONT ACROSS THE REGION NEXT FRIDAY. OF COURSE GIVEN THE GFS RELIABILITY AT DAY EIGHT ONE PROBABLY SHOULD NOT QUITE CANCEL ANY PICNICS JUST YET. && .AVIATION... S OF POINT CONCEPTION...A COMBINATION OF A FAIRLY STRONG INVERSION WITH THE MARINE LAYER 1500 FT DP AND VERY WEAK SFC PRESSURE GRADIENTS HAVE MADE FOR DENSE FOG IN MANY AREAS THIS MORNING. A ANY STRATUS THAT HAS MOVED INTO THE VALLEYS WILL CONTINUE WITH LIFR CIGS AND VSBYS. MOST AREAS ON THE COASTAL PLAIN WILL SEE CIGS AOB 500 FT AS WELL. LOOK FOR CLEARING TO THE BEACHES JUST BEFORE NOON TODAY. VALLEYS SHOULD CLEAR UP BY MID MORNING HOURS. VSBYS SHOULD REMAIN IN MVFR CAT THROUGH MOST OF THE DAY FOR VALLEYS AND COASTAL SECTIONS. N OF POINT CONCEPTION... SANTA MARIA AND SAN LUIS OBISPO AP HAVE BEEN SOCKED IN MOST OF THE NIGHT WITH LIFR CONDS FOR BOTH CIGS AND VSBYS. MODELS KEEP LOW CLOUDS HANGING AROUND NEAR THE COAST MOST OF THE DAY. THIS SEEMS REASONABLE WITH WARM AIR ADVECTION ALOFT...AND LIGHT SFC WINDS TODAY. EXPECT DENSE FOG TO CONTINUE THROUGH MID MORNING HOURS...THEN BURNOFF TO MVFR CONDITIONS FOR THE COASTAL AREAS. EXPECT DENSE FOG TO REDEVELOP ONCE AGAIN IN THE EARLY EVENING HOURS. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXCWFLOX). && $$ PUBLIC...MOYER/RORKE AVIATION...KAPLAN