FXUS66 KLOX 110531 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
930 PM PST FRI FEB 10 2012

...UPDATED AVIATION DISCUSSION...

.SYNOPSIS...

A WEAK TROUGH WILL BRING WELL BELOW SEASONAL TEMPERATURES AND A 
SLIGHT CHANCE OF SHOWERS TO THE INTERIOR SECTIONS ON SATURDAY.  IT 
WILL BE ANOTHER COOL BUT DRY DAY ON SUNDAY. ANOTHER WEAK LOW 
PRESSURE SYSTEM WILL BRING CLOUDY SKIES AND A CHANCE OF RAIN ON 
MONDAY AND TUESDAY. IT LOOKS TO BE DRY AND WARMER BY MID WEEK.

&&

.SHORT TERM (TONIGHT-MON)...A DISSIPATING COLD FRONT BROUGHT LOW 
CLOUDS AND SOME FOG TO PORTIONS OF THE CENTRAL COAST AND SANTA YNEZ 
VALLEY THIS EVENING. OTHERWISE...FAIR SKIES WITH VARYING AMOUNTS OF 
HI CLOUDS PREVAILED OVER THE REGION. THE BAND OF HI CLOUDS SHOULD 
MOVE E OVERNIGHT AS AN UPPER LEVEL TROF APPROACHES THE AREA. PLENTY 
OF STRATOCU AND LOWER MARINE LAYER CLOUDS WILL CONTINUE TO MOVE INTO 
SLO/SBA COUNTIES OVERNIGHT AND SPREAD FURTHER S INTO L.A./VTU 
COUNTIES. LOCAL GUSTY N WINDS WERE NOTED IN THE SANTA YNEZ RANGE AND 
S SBA COUNTY COAST THIS EVENING...AND LOCALLY GUSTY W WINDS AFFECTED 
THE ANTELOPE VALLEY...OTHERWISE WINDS WERE GENERALLY LIGHT FOR MOST 
AREAS.

THE UPPER TROF IS FORECAST TO MOVE INTO SWRN CA ON SAT THEN MOVE E 
OF THE REGION SAT NIGHT AND SUN...WITH A BROAD NW FLOW ALOFT OVER 
THE REGION FOR THE SECOND HALF OF THE WEEKEND. THERE WILL BE LIMITED 
MOISTURE WITH THE UPPER TROF. IT LOOKS LIKE A FEW SHOWERS AND MTN 
SNOW SHOWERS WILL BE POSSIBLE MAINLY OVER THE INTERIOR PORTIONS OF 
THE FORECAST AREA ON SAT...AND ALONG THE N MTN SLOPES SAT NIGHT. 
OTHERWISE DRY AND COOLER WEATHER IS EXPECTED THRU SUN. MOSTLY CLOUDY 
SKIES WILL PREVAIL INTO SAT NIGHT WITH PARTLY CLOUDY CONDITIONS 
EXPECTED FOR SUN. GUSTY W TO NW WINDS ARE EXPECTED OVER THE CENTRAL 
COAST AND ANTELOPE VALLEY BY SAT AFTERNOON. THESE WINDS SHOULD 
EXPAND INTO THE MTNS AND TURN MORE NW TO N FOR SAT NIGHT. GUSTY W 
WINDS SHOULD AGAIN AFFECT THE ANTELOPE VALLEY BY SUN AFTERNOON. 
TEMPS OVER THE WEEKEND ARE FORECAST TO BE MUCH COOLER AND CLOSER TO 
NORMAL OR EVEN SLIGHTLY BELOW NORMAL.

ANOTHER UPPER LEVEL TROF IS EXPECTED TO MOVE INTO NRN CA WHILE 
STRENGTHENING INTO AN UPPER LOW SUN NIGHT. THIS SYSTEM WILL THEN 
MOVE SE THRU CA ON MON. IT LOOKS LIKE THE UPPER LOW WILL BE 
ACCOMPANIED WITH ENOUGH MOISTURE TO BRING A SLIGHT CHANCE TO CHANCE 
OF SHOWERS TO MUCH OF THE FORECAST AREA BY MON...WITH SNOW SHOWERS 
POSSIBLE OVER THE HIGHER MTN ELEVATIONS. THIS SYSTEM WILL ALSO BRING 
INCREASED ONSHORE FLOW WITH GUSTY W TO NW WINDS FOR MANY AREAS BY 
MON AFTERNOON. TEMPS WILL TURN EVEN COOLER ON MON WITH HIGHS ABOUT 5 
TO 10 DEG BELOW NORMAL.

***FROM PREVIOUS DISCUSSION***        

.LONG TERM (TUE-FRI)...GUIDANCE DIFFERED SIGNIFICANTLY FROM RUN TO 
RUN AS WELL AS BETWEEN SUITES FOR THE TUESDAY THROUGH WEDNESDAY 
PERIODS. THE FULL LATITUDE LONG WAVE RIDGE IS EXPECTED TO PERSIST 
OVER THE AREA THOUGH SHORTWAVE TROUGHS WILL DIFFER IN STRENGTH AND 
TIMING WHILE MOVING THROUGH THE RIDGE. HAVE FOLLOWED THE ENSEMBLE 
AND INDICATED A SLIGHT CHANCE OF LIGHT SHOWERS TUESDAY NIGHT. A 
WARMING TREND IS EXPECTED WEDNESDAY THROUGH FRIDAY AND LIKELY WARM 
TO AROUND NORMAL THURSDAY AND A FEW DEGREES ABOVE NORMAL FRIDAY.  

&&

.AVIATION...11/0530Z...

THE COMBINATION OF A RETURNING MARINE LAYER AND AN APPROACHING WEAK 
STORM SYSTEM WILL MAKE FOR A LOW CONFIDENCE TAF PACKAGE THIS EVENING.
STRATUS IS FILLING IN NICELY ACROSS MOST OF SLO/SBA COUNTIES THIS 
EVENING. SOUTH OF POINT CONCEPTION...A RATHER LARGE BATCH OF HIGH 
CLOUDS HAS DELAYED THE ARRIVAL OF STRATUS. HOWEVER...WITH THESE HIGH 
CLOUDS MOVING OUT IN THE NEXT HOUR OR TWO...STRATUS SHOULD RETURN TO 
COASTAL/VALLEY SECTIONS OF VTU/LAX COUNTIES. WITH RAPIDLY DEEPENING 
MARINE INVERSION...SOME PATCHY DRIZZLE WILL BE POSSIBLE. THESE 
MARINE LAYER CLOUDS WILL LINGER INTO THE AFTERNOON.

AS FOR THE APPROACHING WEAK STORM SYSTEM...WILL EXPECT SOME INCREASE 
IN MID-LEVEL CLOUDS THROUGH THE DAY. THERE WILL BE THE POSSIBILITY 
OF SOME VERY LIGHT SHOWERS THROUGH THIS EVENING...BUT NOTHING 
SIGNIFICANT ENOUGH FOR MENTION IN ANY TAF.

KLAX...LOW CONFIDENCE IN 06Z TAF. TIMING/HEIGHT OF STRATUS RETURN 
SATURDAY MORNING IS LOW CONFIDENCE FORECAST. 

KBUR...LOW CONFIDENCE IN 06Z TAF. TIMING/HEIGHT OF STRATUS RETURN 
SATURDAY MORNING IS A LOW CONFIDENCE FORECAST. 

&&

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

&&

$$

PUBLIC...SIRARD/30
AVIATION...RAT
SYNOPSIS...BARTLING

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