FXUS66 KLOX 050510
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
910 PM PST SAT FEB 4 2012

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY WITH SOME
NORTHEAST WINDS AND ABOVE NORMAL TEMPERATURES. A LOW PRESSURE SYSTEM
WILL MOVE ACROSS THE AREA TUESDAY AND WEDNESDAY...BRINGING THE
POTENTIAL FOR RAINFALL AND GUSTY WINDS. HIGH PRESSURE WILL BUILD
OVER THE AREA ONCE AGAIN BY LATE WEEK...BRINGING A RETURN OF ABOVE
NORMAL TEMPERATURES AND SOME GUSTY NORTHEAST WINDS.

&&

.SHORT TERM (TONIGHT-TUE)...GENERALLY CLEAR SKIES COVERED THE
FORECAST AREA THIS EVENING WITH JUST A FEW HI CLOUDS HERE AND
THERE...AND LITTLE CHANGE IS EXPECTED OVERNIGHT. OFFSHORE FLOW HAS
CONTINUED THIS EVENING WITH THE HIGHEST GUSTS OVER PORTIONS OF
L.A./VTU COUNTIES OF 30 TO 35 MPH AT TIMES. THERE MAY BE A FEW
ISOLATED GUSTS TO 40 MPH OVERNIGHT... OTHERWISE WINDS ARE EXPECTED
TO REMAIN LARGELY BELOW ADVISORY LEVELS FOR THE AREAS THAT HAVE
BREEZY CONDITIONS...MAINLY THE VALLEYS AND MTNS OF VTU/L.A.
COUNTIES.

AN UPPER LEVEL RIDGE JUST OFF THE COAST WILL BUILD VERY SLOWLY E
THRU SUN WHILE GRADUALLY WEAKENING. WEAK UPPER RIDGING SHOULD THEN
MOVE INTO SRN CA SUN NIGHT AND MON. MOSTLY CLEAR SKIES WILL PREVAIL
ACROSS SWRN CA THRU SUN...ALTHO A FEW HIGH CLOUDS SHOULD MOVE OVER
THE AREA FROM TIME TO TIME. THE HI CLOUDS SHOULD BECOME A BIT MORE
EXTENSIVE BY MON WITH PARTLY CLOUDY SKIES EXPECTED. THE OFFSHORE
FLOW WILL CONTINUE MAINLY NIGHT AND MORNING HOURS OVER THE REGION.
FAIRLY GUSTY WINDS CAN BE EXPECTED TO CONTINUE OVER PORTIONS OF
L.A./VTU COUNTIES SUN MORNING...WITH WEAKER OFFSHORE WINDS SUN NIGHT
INTO MON MORNING. AS AN UPPER LEVEL TROF APPROACHES FROM THE E PAC
ON MON...THE OFFSHORE FLOW IS EXPECTED TO WEAKEN MON MORNING...WITH
ONSHORE FLOW INCREASING MON AFTERNOON. THE COMBINATION OF SOME UPPER
LEVEL RIDGING AND OFFSHORE FLOW WILL BRING ABOVE NORMAL TEMPS TO
MOST OF THE REGION AGAIN ON SUN...WITH HIGHS REACHING INTO THE MID
70S IN THE WARMEST VALLEYS. TEMPS ARE EXPECTED TO TURN SLIGHTLY
COOLER ON MON WITH INCREASING ONSHORE FLOW AND THE HI CLOUDS MOVING
IN...ALTHO HIGHS WILL CONTINUE SLIGHTLY ABOVE NORMAL FOR THE MOST
PART EXCEPT ON THE CENTRAL COAST.

AN EASTERN PAC UPPER TROF IS FORECAST TO APPROACH THE CENTRAL CA
COAST MON NIGHT AND TUE MORNING. AN UPPER LEVEL LOW WILL DEVELOP AT
THE BASE OF THE UPPER TROF BY TUE AFTERNOON AND MOVE TO JUST OFF
POINT CONCEPTION BY LATE TUE. THE 00Z WRF AND GFS ARE IN REASONABLE
AGREEMENT WITH ONLY MINOR DIFFERENCES IN THE POSITION OF THE UPPER
LOW TUE AFTERNOON. A COLD FRONT ASSOCIATED WITH THE UPPER TROF WILL
MOVE INTO THE CENTRAL COAST BY ABOUT MIDDAY TUE...THEN THE FRONT
SHOULD PUSH INLAND AND FURTHER S INTO VTU/L.A. COUNTIES BY LATE IN
THE DAY. IT LOOKS LIKE RAIN WILL START TO DEVELOP ALONG THE CENTRAL
COAST BY LATE MON NIGHT THEN SPREAD E AND S THRU THE MORNING...WITH
RAIN BECOMING LIKELY FOR MANY AREAS TUE AFTERNOON. SNOW LEVELS ARE
EXPECTED TO FALL TO AROUND 5500 TO 6000 FEET BY TUE AFTERNOON...WITH
SOME ACCUMULATING SNOW POSSIBLE ABOVE 6000 FEET. GUSTY S TO SE WINDS
WILL ALSO ACCOMPANY THE FRONT TUE MORNING INTO THE AFTERNOON...
ESPECIALLY OVER PORTIONS OF SLO/SBA COUNTIES AND ACROSS HIGHER
TERRAIN OF VTU/L.A. COUNTIES. IT LOOKS LIKE THE ATMOSPHERE WILL
BECOME A BIT UNSTABLE ESPECIALLY CLOSER TO THE COAST AND OVER THE
COASTAL WATERS ON TUE. ALONG WITH SOME DIFFLUENT FLOW ALOFT...-22
DEG C TEMPS AT 500 MB...AND A 120 KT JET JUST OFF THE COAST...THE
SLIGHT CHANCE OF THUNDERSTORMS CANNOT BE RULED OUT FOR PORTIONS OF
THE FORECAST AREA AND COASTAL WATERS BY TUE AFTERNOON. PRELIMINARY
RAINFALL ESTIMATES FOR MON NIGHT THRU TUE ARE FOR ONE QUARTER TO ONE
HALF INCH FOR COASTAL AND VALLEYS AREAS...WITH ONE HALF TO ONE INCH
FOR THE MOUNTAINS. LOCALLY HIGHER RAINFALL AMOUNTS UP TO AN INCH
CANNOT BE RULED OUT FOR FAR NWRN SLO COUNTY. NEEDLESS TO SAY...TEMPS
ON TUE WILL BE MUCH COOLER...FALLING TO SEVERAL DEGREES BELOW NORMAL
TO NEAR NORMAL.

***FROM PREVIOUS DISCUSSION***

.LONG TERM (WED-SAT)...THE LOW IS FORECAST TO MIGRATE SOUTH OF THE
AREA WEDNESDAY INTO THURSDAY. WITH THE SLOWER GFS SOLUTION...BELIEVE
SOME WRAP AROUND MOISTURE COULD KEEP SHOWERS GOING OVER SOUTHERN
INTERIOR SECTIONS ON WEDNESDAY. BY THURSDAY BOTH GFS AND ECMWF SHIFT
THE LOW CENTER TO CENTRAL BAJA...WITH UPPER RIDGING BUILDING INTO
CALIFORNIA. BUILDING HIGH PRESSURE IS EXPECTED TO PRODUCE A WARMING
AND DRYING TREND THROUGH LATE IN THE WEEK...ALONG WITH BREEZY
OFFSHORE WINDS. BY SATURDAY THE MODELS BRING ANOTHER TROUGH TO/NEAR
THE COAST DEPENDING ON WHICH SOLUTION YOU CHOOSE. FOR NOW KEPT POPS
BELOW SLIGHT CHANCE FOR SATURDAY BUT INDICATED A SLIGHT INCREASING
TREND.

&&

.AVIATION...04/2350Z...HI CONFIDENCE IN THE CURRENT TAF PACKAGE WITH
VFR CONDITIONS EXPECTED THRU SUN AT ALL AIRFIELDS. GUSTY NE WINDS
WILL PREVAIL AT KPMD AND KWJF THROUGH EARLY THIS EVENING.

KLAX...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS EXPECTED
THRU SUN EVENING.

KBUR...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS EXPECTED
THRU SUN.

&&

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

&&

$$

PUBLIC...SIRARD/SMITH
AVIATION...SIRARD
SYNOPSIS...RAT

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