FXUS66 KLOX 221233
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
420 AM PST TUE DEC 22 2009

...NEW AVIATION DISCUSSION...

.SYNOPSIS... 

COLD AND WINDY...WITH A CHANCE OF RAIN MAINLY NORTH OF POINT 
CONCEPTION AND OVER THE GRAPEVINE THROUGH THIS MORNING AS AN 
ENERGETIC LOW SWEEPS OUT OF THE AREA. STRONG, GUSTY WINDS WILL 
AFFECT MOUNTAINS, PASSES, CANYONS AND THE GRAPEVINE. MOSTLY CLEAR 
SKIES AND A WARMING TREND THROUGH CHRISTMAS THEN A STORM SYSTEM MAY 
APPROACH EARLY NEXT WEEK WITH A CHANCE OF RAIN AND A COOLING TREND.  

&&

.SHORT TERM (TODAY-THU)...
FORECAST GOING PRETTY MUCH AS PLANNED. THE COLD FRONT HAS GONE 
THROUGH THE AREA AND A FEW POST FRONTAL SHOWERS ARE MILLING 
ABOUT...ESPECIALLY OVER THE CENTRAL COAST AND THE NORTH SLOPES. THE 
SHOWERS ACROSS THE NORTHERN SLOPES WILL CONTINUE THROUGH THE DAY AND 
DUE TO ALL OF THE COLD AIR POURING IN THE SNOW LEVELS WILL BE VERY 
LOW...BETWEEN 3000 AND 4000 FEET. THERE WILL BE LITTLE IN THE WAY OF 
RAIN OR SNOWFALL ACCUMULATIONS.

THE WINDS ARE THE BIG STORY AS THE JET STREAM IS ORIENTED DUE NORTH 
TO SOUTH OVER THE STATE. THE UPPER SUPPORT...COLD AIR ADVECTION AND 
GOOD NORTH TO SOUTH PRESSURE GRADIENT WILL ALL COMBINE TO PRODUCE A 
VERY WINDY DAY. THE BRUNT OF THE WINDS WILL BE FELT IN THE MTNS 
WHERE GUSTS TO 40 MPH WILL BE POSSIBLE. THE STRONGEST WINDS IN THE 
SAN FERNANDO VLY WILL BE IN THE WESTERN PORTION. ADDED WIND 
ADVISORIES TO ALL AREAS NOT COVERED BY WIND WARNINGS...REFER TO 
LAXNPWLOX FOR FULL DETAILS ON TIMING AND LOCATION OF TODAYS AND THIS 
EVENINGS WINDS.

THE WINDS WILL SUBSIDE OVERNIGHT AND WILL TURN TO THE NORTHEAST. BY 
MORNING THE FAVORED NORTHEAST WINDY LOCATIONS WILL SEE 15 TO 25 MPH. 
WITH ALL THE COLD AIR POURING IN AND THKNS LOWERING TO 545 DM 
OVERNIGHT LOWS IN WIND SHELTERED AREAS WILL DROP TO NEAR FREEZING 
AND FROST ADVISORIES WILL LIKELY BE NEEDED FOR A FEW LOCATIONS THAT 
HAVE NOT ALREADY HAD TWO OR MORE PREVIOUS FROST EVENT.

AFTER A CHILLY MORNING WEDNESDAYS TEMPS WILL BEGIN TO WARM AS A 
RIDGE BEGINS TO BUILD IN.

THE WEATHER WILL TAKE A DECIDED TURN FOR THE BETTER CHRISTMAS EVE 
WITH A RIDGE BUILDING IN AND WEAK OFFSHORE FLOW FORMING AT THE 
SURFACE. THE WEATHER SHOULD BE MOSTLY CLEAR WITH A FEW MORNING 
CANYON BREEZES. MAX TEMPS WILL BE AT OR MAYBE EVEN A DEGREE OR TWO 
ABOVE SEASONAL NORMALS.

.LONG TERM (FRI-MON)...

EC AND GFS ARE IN GOOD AGREEMENT THROUGH SATURDAY AND THE PLEASANT 
WEATHER WILL CONTINUE WITH A NICE RIDGE IN PLACE AND WEAK OFFSHORE 
FLOW. TEMPS WILL CONTINUE TO REMAIN RIGHT AT NORMALS.

ALL MDLS POINT A SIGNIFICANT SHIFT IN THE WEATHER PATTERN SUNDAY AND 
MONDAY BUT ALSO CONTINUE TO DIFFER ON THE DETAILS. CURRENT FORECAST 
WITH CHC TO SLGT CHC WORDING AND MOSTLY CLOUDY SKIES SEEMS GOOD 
UNTIL THE MDLS BEGIN TO CONVERGE. TEMPS WILL TAKE A FAIRLY DRAMATIC 
DIP.

&&

.AVIATION...

22/1200Z

CHAOTIC MANY LAYERED CLOUD PATTERN WILL PRODUCE HIGH MVFR TO LOW VFR 
CONDS THROUGH MID MORNING. CLOUDS WILL BEGIN TO THIN OUT AFTERWORDS 
AND SKIES SHOULD BE MOSTLY CLEAR BY AFTERNOON. WINDS WILL BE THE BIG 
PLAYER TODAY WITH STRONG NORTH TO NORTHWEST WINDS ACROSS THE ENTIRE 
AREA TODAY AND WILL PRODUCE MDT-SVR TURBC ACROSS AND NEAR TO THE 
MTNS.

KLAX...GOOD CONFIDENCE IN TAF.

KBUR...GOOD CONFIDENCE IN TAF. MDT ISOLD SVR TURBC SFC-070.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING (SEE LAXNPWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
GALE WARNING (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).

&&

$$

PUBLIC...RORKE
AVIATION...BRUNO
SYNOPSIS...ASR

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