922 
FXUS66 KLOX 022329
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
330 PM PST MON JAN 2 2012

.SYNOPSIS...
WARM DAYTIME HIGHS AND COOL TEMPERATURES AT NIGHT WILL CONTINUE 
THROUGH MUCH OF THE WEEK UNDER THE INFLUENCE OF HIGH PRESSURE. 
CONDITIONS WILL REMAIN DRY FOR THE FORESEEABLE FUTURE. BY FRIDAY AND 
INTO THE UPCOMING WEEKEND...HIGH TEMPERATURES WILL COOL BY ABOUT 5 
TO 10 DEGREES.
 
&&

.SHORT TERM (TODAY-THU)...HIGH PRESSURE ALOFT CONTINUES TO DOMINATE 
THE WEATHER PATTERN LOCALLY AS THE STORM TRACK REMAINS WELL NORTH OF 
THE STATE. A SYSTEM PASSING THROUGH THE PAC NW TODAY WILL DRAG SOME 
HIGH CLOUDS THROUGH THE AREA TONIGHT AND TUESDAY BUT LATEST MODELS 
NOW MOVE THIS THROUGH MUCH FASTER RATHER THAN LINGER THEM THROUGH 
WEDNESDAY. HOWEVER, THESE HIGH CLOUDS MAY BE QUITE THICK AT TIMES 
ACROSS THE AREA TUESDAY, POSSIBLY ENOUGH TO SHAVE SOME DEGREES OF 
HIGH TEMPS. THE OTHER POTENTIAL IMPACT WILL BE THE MARINE LYR, WHICH 
OFTEN, THOUGH NOT ALWAYS, MAKES AN ABRUBT EXIT WITH ABUNDANT HIGH 
LEVEL MOISTURE. LATEST VISIBLE SATELLITE TRENDS TEND TO FAVOR THIS 
SCENARIO, WITH LOW CLOUDS RAPIDLY MOVING SOUTH OUT OF THE FORECAST 
AREA THIS AFTERNOON. THE HIGHER LEVEL MOISTURE IS OBSCURRING THE 
PICTURE NORTH OF PT CONCEPTION BUT I SUSPECT THERE IS JUST SOME 
PATCHY LOW CLOUDS/FOG LINGERING THERE AT BEST, AND POSSIBLY NONE AT 
ALL. CONFIDENCE EXTREMELY LOW ON WHAT WILL HAPPEN TONIGHT IN TERMS 
OF THE MARINE LYR. CURRENT TRENDS WOULD CERTAINLY PORTEND A MINIMAL 
FOG FORECAST AT BEST BUT GIVEN THE SLIGHT ONSHORE TRENDS IN THE 
GRADIENTS AND CURRENT LOW DEWPOINT DEPRESSIONS ACROSS THE COASTAL 
AREAS I THINK THERE IS STILL A CHANCE WE COULD SEE A FAIR AMOUNT OF 
DENSE FOG DEVELOPING BY LATER TONIGHT. WILL NOT BE ISSUING AN 
ADVISORY WITH THE AFTERNOON FORECAST GIVEN THE LOW CONFIDENCE AND 
LIKELY VERY LATE DEVELOPMENT AT BEST.

FORECAST HIGHS FOR COASTAL AREAS WILL REMAIN VERY DIFFICULT AS THERE 
IS A VERY FINE LINE BETWEEN THE COLD MARITIME AIR AND THE WARM 
INTERIOR AIR FROM THE OFFSHORE FLOW. TODAY THAT LINE SHIFTED A FEW 
MILES INLAND AND KEPT MANY INTERIOR COASTAL LOCATIONS FROM REACHING 
80. GIVEN THAT THE OFFSHORE FLOW WILL BE A TAD WEAKER TUESDAY I 
WOULD THINK COASTAL TEMPS WILL SEE LITTLE CHANGE FROM TODAY, THOUGH 
MOS GUIDANCE IS MUCH WARMER AND THE EXITING LOW CLOUDS TO THE SOUTH 
MAKES ME WONDER IF MODELS ARE OVERDOING THE ONSHORE TRENDS FOR 
TOMORROW. IN ANY CASE, A TOUGH COASTAL FORECAST FOR TEMPS. INLAND 
FROM THIS SHIFTING BOUNDARY TEMPS WILL REMAIN WARM, WITH EVEN 
OVERNIGHT TEMPS IN MANY AREAS REMAINING IN THE 60S, ESECIALLY IN THE 
HILLS. AGAIN THE HIGH CLOUDS MAY KNOCK A FEW DEGREES OF THESE 
NUMBERS TUESDAY, BUT STILL WELL ABOVE NORMAL. 

ON WEDNESDAY THERE IS ANOTHER LITTLE SURGE IN OFFSHORE FLOW THAT MAY 
BE ENOUGH TO SHIFT THAT MARITIME BOUNDARY A FEW MILES WEST AND ALLOW 
SOME COASTAL AREAS TO WARM BACK UP INTO THE 70S AND POSSIBLY EVEN 
80S. WARMER ALSO FOR INLAND AREAS AS NORTHEAST WINDS STRENGTHEN A 
BIT AND HIGH PRESSURE ALOFT BUILDS. 

TODAY'S MODELS INDICATED POSSIBLY A ONE DAY DELAY IN THE BIG COOLING 
TREND FOR THE END OF THE WEEK. GRADIENTS WILL BE TRENDING PRETTY 
STRONGLY ONSHORE BY THURSDAY AFTERNOON, BUT POSSIBLY NOT EARLY 
ENOUGH TO KEEP INLAND AREAS FROM WARMING UP TO NEAR WEDNESDAY'S 
LEVELS. 

.LONG TERM (FRI-MON)...NOT MUCH CHANGE HERE AS MODELS CONTINUE TO 
ADVERTISE STRONG ONSHORE FLOW RETURNING FRIDAY FOR MUCH COOLER 
TEMPS, THEN A DRY "INSIDE SLIDER" TYPE SYSTEM FOR SAT/SUN. THIS WILL 
INITIALLY BRING DECENT NORTHWEST FLOW TO THE AREA EARLY IN THE 
WEEKEND, THEN SHIFTING NORTHEAST SUNDAY AS HIGH PRESSURE DEVELOPS 
ACROSS THE INTERIOR. POSSIBLY NEAR ADVISORY LEVEL WINDS AT TIMES, 
ESPECIALLY IN THE MOUNTAINS. SOME WARMING LIKELY AT LOWER ELEVATIONS 
SUNDAY/MONDAY BUT THE AIR MASS WILL STILL BE MUCH COOLER THAN IT IS 
NOW SO HIGHS AREN'T LIKELY TO TOP THE LOWER 70S THROUGH EARLY NEXT 
WEEK. THE FORECAST REMAINS DRY THROUGH AT LEAST THE MIDDLE OF NEXT 
WEEK.

&&

.AVIATION...02/2330Z.
INFLUX OF HIGHER LEVEL CLOUDS ACROSS THE REGION THIS AFTERNOON...WITH
LOW CLOUDS AND FOG CLEARING WELL OFF THE COAST. DUE TO THE GOOD 
BURNOFF...CONFIDENCE IS LOWER FOR RETURN OF LOW CLOUDS AND FOG RETURNING
TO COASTAL AREAS OVERNIGHT. IF ANY FOG DOES DEVELOP...THERE WILL STILL
BE THE POTENTIAL FOR VLIFR CONDITIONS DUE TO LOW AND STRONG INVERSION
IN PLACE. FOR NOW...HAVE TRENDED BACK TIMING FOR RETURN OF FOG
IN CURRENT TAF PACKAGE...GENERALLY AFTER 08Z. BUT ONCE AGAIN...CONFIDENCE
IS LOWER TONIGHT FOR THE RETURN OF WIDESPREAD DENSE FOG.

KLAX...CONFIDENCE IS NOW LOWER FOR THE RETURN OF DENSE FOG TO KLAX
OVERNIGHT AS SATELLITE IMAGERY CONTINUES TO SHOW LOW CLOUDS AND FOG
RETREATING WELL OFFSHORE THIS AFTERNOON. HOWEVER...IF DENSE FOG WERE 
TO REFORM...IT WOULD MOST LIKELY OCCUR BETWEEN 08Z-15Z. 

KBUR...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH PERIOD.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

$$

PUBLIC...WOFFORD
AVIATION...GOMBERG
SYNOPSIS...SWEET

WWW.WEATHER.GOV/LOSANGELES