FXUS66 KLOX 260448
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
850 PM PST WED NOV 25 2009
.SYNOPSIS...
WARM AND DRY OFFSHORE WINDS WILL CONTINUE THROUGH THANKSGIVING. A
WEAK COLD FRONT WILL MOVE ACROSS THE AREA ON FRIDAY...BRINGING
NOTICEABLY COOLER TEMPERATURES ON FRIDAY AND SATURDAY AS WELL AS
CHANCE OF RAIN AND SNOW SHOWERS IN THE MOUNTAINS. BY SUNDAY AND INTO
EARLY NEXT WEEK...ANOTHER ROUND OF OFFSHORE WINDS WILL ONCE AGAIN
PRODUCE DRY AND WINDY CONDITIONS ACROSS THE AREA WITH A WARMING
TREND.
&&
.SHORT TERM (TONIGHT-SAT)...GUSTY NE CANYON WINDS CONTINUED THIS
EVENING MAINLY OVER THE VTU/L.A. COUNTY MTNS...THE SANTA CLARITA
VALLEY AND THE VTU COUNTY VALLEYS. WINDS WERE MOSTLY BELOW ADVISORY
LEVELS...WITH A FEW GUSTS EXCEEDING ADVISORY LEVELS AT TIMES. LITTLE
CHANGE IS EXPECTED OVERNIGHT WITH THE GUSTY WINDS PERSISTING AND
REMAINING MAINLY BELOW ADVISORY LEVELS. CLEAR SKIES THIS EVENING IN
ALL AREAS WILL PREVAIL OVERNIGHT AS WELL.
UPPER RIDGING WILL LINGER OVER CA ON THANKSGIVING. A BROAD UPPER
LEVEL TROUGH WILL APPROACH THE FORECAST AREA FROM THE E PAC THU
NIGHT AND FRI. THE UPPER TROF IS EXPECTED TO STRENGTHEN INTO AN
UPPER LEVEL LOW ALONG THE CENTRAL CA COAST FRI NIGHT THEN MOVE INTO
SOUTHERN CA ON SAT. THE GFS WAS A BIT MORE INLAND WITH THIS UPPER
LOW COMPARED WITH THE WRF...WHICH MOVED THE UPPER LOW TO THE L.A.
COUNTY COAST ON SAT. DRY WEATHER IS EXPECTED OVER THE DISTRICT
THROUGH FRIDAY. MOSTLY CLEAR SKIES WILL CONTINUE IN ALL AREAS THRU
THANKSGIVING. SOME LOW CLOUDS AND FOG MAY AFFECT THE CENTRAL COAST
THU NIGHT INTO FRI MORNING...OTHERWISE CLEAR TO PARTLY CLOUDY SKIES
WILL PREVAIL OVER THE DISTRICT THU NIGHT AND FRI. GUSTY NE CANYON
WINDS THANKSGIVING MORNING WILL WEAKEN DURING THE AFTERNOON...WITH
MUCH WEAKER FLOW THU NIGHT INTO FRI MORNING. TEMPS WILL AGAIN BE
QUITE A BIT WARMER THAN NORMAL OVER THE REGION FOR THANKSGIVING...
THEN COOL SIGNIFICANTLY AND BACK TO NEAR NORMAL OR SLIGTHLY BELOW
NORMAL ON FRI.
THE POSITION AND MOVEMENT OF THE UPPER LOW FRI NIGHT AND SAT WILL
HAVE CERTAIN REPERCUSSIONS ON THE WEATHER OVER THE DISTRICT. IF IT
MOVES FURTHER INLAND THAN THE CURRENT FORECAST OF A CHANCE OF
SHOWERS MAINLY OVER THE EASTERN PARTS OF THE DISTRICT LOOK
REASONABLE. IF THE UPPER LOW MOVES OVER THE FORECAST AREA AS THE WRF
INDICATES THERE WOULD BE A MORE SIGNIFICANT CHANCE OF RAIN AND
MOUNTAIN SNOW SHOWERS DURING THE PERIOD...AND POSSIBLY EVEN SNOW
SHOWERS INTO THE FOOTHILLS OF THE ANTELOPE VALLEY. AN ISOLATED
THUNDERSTORM WOULD ALSO BE POSSIBLE. I WILL NOT MAKE ANY CHANGES TO
THE FORECAST FOR FRI NIGHT AND SAT AT THIS TIME AS CONFIDENCE IN ANY
ONE SOLUTION IS LOW...WITH FURTHER MODEL RUNS NEEDED TO FINE TUNE
THE FORECAST. AT ANY RATE...TEMPS OVER THE REGION WILL TURN COOLER
STILL FOR SAT...AND BE SEVERAL DEGREES BELOW NORMAL IN ALL AREAS.
...FROM PREVIOUS DISCUSSION...
.LONG TERM (SUN-WED)...THIS PORTION OF THE FORECAST REMAINS
RELATIVELY UNSCATHED FROM YESTERDAY WITH MODERATE TO STRONG OFFSHORE
FLOW DEVELOPING BEHIND THE TROF. WARMING WILL BE MINIMAL INITIALLY
DUE TO THE LINGERING COLD AIR FROM THE UPPER LOW, HOWEVER EACH DAY
THROUGH WED SHOULD WARM UP A COUPLE DEGREES, WITH MID 70S BY THE
MIDDLE OF THE WEEK. AT THIS TIME THIS APPEARS TO AT LEAST BE AN
ADVISORY LEVEL WIND EVENT, AND POSSIBLY WARNING LEVEL FOR THE MTNS.
&&
.AVIATION...26/0435Z....HI CONFIDENCE IN ALL CURRENT TAFS. GUSTY N
CANYON WINDS WILL PERSIST AT TIMES AT KVNY...AND PERIODS OF LOW
LEVEL WIND SHEAR WILL BE POSSIBLE AT KBUR.
KLAX...HIGH CONFIDENCE IN CURRENT TAF.
KBUR...HIGH CONFIDENCE IN CURRENT TAF. PERIODS OF LOW LEVEL WIND
SHEAR WILL BE POSSIBLE TONIGHT AND THU MORNING DUE TO GUSTY N TO NE
CANYON WINDS IN THE VICINITY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY (SEE LAXCFWLOX).
&&
$$
PUBLIC...SIRARD/WOFFORD
AVIATION...SIRARD
SYNOPSIS...WOFFORD
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