FXUS66 KLOX 080442
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
845 PM PST MON DEC 7 2009
.SYNOPSIS...
GUSTY WINDS WITH RAIN OR SNOW...ABOVE 1500 FEET...OVERNIGHT THEN
PARTLY CLOUDY EXCEPT ON THE NORTH SLOPES BY TUESDAY MORNING.
EXTREMELY COLD TEMPERATURES ARE EXPECTED TONIGHT AND AGAIN TUESDAY
NIGHT. A STORM SYSTEM WILL BRING A CHANCE OF RAIN FOR THURSDAY...AND
ANOTHER STORM IS FORECASTED TO BRING RAIN INTO THE WEEKEND.
&&
.SHORT TERM (TODAY-THU)...
SAVE FOR THE NORTH SLOPES OF THE MTNS AND THE CUYAMA VALLEY SKIES
HAVE TURNED PARTLY CLOUDY IN THE WAKE OF THIS AFTERNOONS COLD FRONT.
THE RAIN HAS SUBSIDED ALMOST EVERYWHERE AND THE MAIN CONCERN HAS
SWITCHED TO THE WINDS AND THE COLD. DUE TO THE LACK OF RAINFALL THE
FLOOD WATCH WAS CANCELLED. HIGH WIND WARNINGS ARE IN EFFECT FOR THE
SBA MTNS...SBA SOUTH COAST AND THE ANTELOPE VLY (HIGH WINDS ARE ALSO
IN THE L.A./VTA MTNS WHICH IS COVERED BY THE WINTER STORM WARNING)
WIND ADVISORIES COVER THE REST OF THE VTA AND LA COASTS AND VLYS.
THE STRONGEST WINDS WILL BE THROUGH THE SAN MARCOS PASS...THE I-5
CORRIDOR AND THE WESTERN FOOTHILLS OF THE ANTELOPE VLY. THE WINDS
ARE THE RESULT OF THE COLD AIR POURING IN BEHIND THE COLD FRONT.
ONCE THE BULK OF THE COLD AIR HAS MOVED IN MANY OF THE ADVISORIES
WILL EXPIRE LATER THIS EVENING AND THE REST ARE SLATED TO EXPIRE
EARLY TUESDAY MORNING.
ACROSS THE NORTHERN SLOPES OF THE MTNS THE NORTH WINDS WILL CONTINUE
TO PILE UP CLOUDS AND CREATE SNOW SHOWERS. THESE SHOWERS COULD
PRODUCE AN ADDITIONAL 4 TO 6 INCHES OF SNOW. SNOW LEVELS WILL LOWER
TO 1500 TO 2000 FEET WHICH WILL ALLOW SNOW TO FALL TO THE CUYAMA VLY
FLOOR.
OVERNIGHT LOWS TONIGHT WILL BE DOWNRIGHT COLD. BY SUNRISE 950 MB
TEMPS INLAND REACH -3C AND 2-3C AT THE COASTS. THE WINDS TONIGHT
WILL KEEP MOST AREAS FROM DIPPING TOO LOW...BUT IN ANY WIND
SHELTERED AREA TEMPS WILL DROP. FROST IS POSSIBLE ANYWHERE EXCEPT
THE SBA SOUTH COAST...THE VTA AND L.A COASTS.
...FROM PREVIOUS DISCUSSION...
TUESDAY WILL BE DRY (EXCEPT EARLY MORNING LINGERING SHOWERS IN THE
MOUNTAINS) AND COLD. MAY BE SOME AFTERNOON STRATOCUMULUS CLOUDS FOR
PC SKIES. HIGHS WILL BE SEVERAL DEGREES BELOW NORMALS. OVERNIGHT
LOWS TONIGHT WILL BE DEPENDENT ON THE WINDS BUT THE CENTRAL COAST IS
MOST AT RISK FOR WIDESPREAD FROST. INLAND SLO COUNTY AND ANTELOPE
VALLEY HAVE ALREADY HAD MULTIPLE FREEZE EVENTS THIS SEASON AND THUS
ARE NO LONGER CONSIDERED FOR FREEZE WARNINGS AND/OR FROST
ADVISORIES. TUESDAY NIGHT SHOULD ACTUALLY BE COLDER, ESPECIALLY IN
LA/VENTURA COUNTIES AS WINDS WILL BE LOWER AND CLOUDS WILL BE
LARGELY ABSENT. HAVE ISSUED FREEZE WATCHES FOR MANY LOWER ELEVATION
AREAS ON TUESDAY NIGHT, INCLUDING VENTURA AND LA COUNTY VALLEYS,
THOUGH ULTIMATELY WE MAY ONLY MEET FROST ADVISORY CRITERIA IN THOSE
AREAS WITH THE EXCEPTION OF SOME ISOLATED POCKETS BELOW 29.
ANOTHER DRY DAY WED WITH JUST A SLIGHT INCREASE IN DAYTIME HIGHS.
WE'LL START SEEING AN INCREASE IN MID AND HIGH CLOUDS AS MOISTURE
MOVES IN FROM THE WEST WELL AHEAD OF OUR NEXT WEATHER SYSTEM. THAT
SYSTEM IS EXPECTED TO ARRIVE ON THURSDAY AND THURSDAY EVENING,
THOUGH THE LATEST MODEL RUNS ARE INDICATING A WEAKER STORM THAN THE
ONE OVER US CURRENTLY. IT ALSO IS CONSIDERABLY WARMER AND DO NOT
ANTICIPATE ANY WINTER OR FLOOD HEADLINES FOR THAT EVENT.
.LONG TERM (FRI-MON)...TIMING STILL AN ISSUE WITH THE WEATHER THIS
WEEKEND. THE THURSDAY EVENT SHOULD BE TAPERING OFF EARLY FRIDAY BUT
ANOTHER SYSTEM IS PRETTY QUICK ON ITS HEELS SO PROBABLY NOT TOO MUCH
OF A BREAK IN THE WET WEATHER. THOUGH AGAIN IT DOES NOT LOOK LIKE A
MAJOR EVENT. THE GFS SHOWS THE FLOW TURNING MORE NORTHWESTERLY OVER
THE WEEKEND WHICH IS NOT QUITE AS FAVORABLE FOR RAIN SOUTH OF PT
CONCEPTION, BUT DO NOT HAVE ENOUGH FAITH IN THE MODELS THAT FAR OUT
TO NOT INCLUDE AT LEAST A CHANCE OF SHOWERS ALL AREAS. SO THE
WEEKEND FORECAST PROBABLY LOOKS GLOOMIER IN WORDS THAN IT WILL BE IN
REALITY, BUT NEED SOME MORE MODEL RUNS BEFORE CONFIDENCE IS HIGH
ENOUGH TO GET MORE SPECIFIC WITH THE TIMING AND POPS.
&&
.AVIATION...07/2350Z.
LAST BAND OF ORGANIZED RAIN WILL MOVE THROUGH THE AREA BY 01Z.
SCT025-045 DECKS WITH A FEW -SHRA WILL PREVAIL AFTER...WITH ONLY
OCCASIONAL MVFR CIGS. WINDS NOW MAIN CONCERN...AND MODERATE
CONFIDENCE EXISTS ON TIMING AND STRENGTH OF WIND. LLWS SHOULD BE A
CONCERN AT KSBA 03Z AND 09Z...WITH AN OUTSIDE SHOT AT KBUR KVNY KOXR
KLAX AND KLGB. WINDS SHOULD START TO RELAX AFTER 08Z OR SO. VERY
STRONG WINDS EXPECTED AT KWJF...AND GUSTS INTO THE 40KT RANGE IS
POSSIBLE.
KLAX...MODERATE CONFIDENCE IN WIND SHIFT AND ACCELERATION TIMING.
LLWS MAY BE A CONCERN...ESPECIALLY LATER TONIGHT AS SURFACE WINDS
RELAX BUT WINDS ALOFT PERSIST.
KBUR...OTHER THAN A FEW SHOWERS THROUGH 04Z...MAIN RAIN SHOULD END
BY 02Z. LOW TO MODERATE CONFIDENCE ON WIND FORECAST. LIKELY TO GET
SOME GUSTY SURFACE NW WINDS...BUT COULD OCCASIONALLY RELAX AND
BECOME A LLWS CONCERN. THIS WILL LAST THROUGH MOST OF THE NIGH
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING (SEE LAXWSWLOX).
HIGH WIND WARNING (SEE LAXNPWLOX).
FLOOD WATCH FOR LA COUNTY BURN AREAS (SEE LAXFFALOX).
WIND ADVISORY (SEE LAXNPWLOX).
GALE WARNING (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
&&
$$
PUBLIC...WOFFORD
AVIATION...KITTELL
SYNOPSIS...MEIER
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