LAXAFDLOX (05/14/13 0432)

FXUS66 KLOX 141135 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
430 AM PDT TUE MAY 14 2013

UPDATED AVIATION SECTION

.SYNOPSIS...

LOW PRESSURE WILL WILL BRINGING COOLER TEMPERATURES AND INCREASING 
NIGHT AND MORNING CLOUDS AND FOG THROUGH THE END OF THE WEEK. 
ANOTHER RIDGE OF HIGH PRESSURE IS EXPECTED TOWARD THE END OF THE 
WEEKEND...BRINGING BACK WARMER TEMPERATURES.

&&

.SHORT TERM (TODAY-FRI)...
BIG WEATHER CHANGE ON TAP FOR TODAY AS YESTERDAYS HIGH PRESSURE WILL 
BE REPLACED BY A WEAK TROF AND THE OFFSHORE FLOW WILL TURN ONSHORE 
AND INCREASE THROUGH THE DAY. THE MARINE LAYER STRATUS HAS NOT 
FORMED YET SOUTH OF POINT CONCEPTION BUT SOME CLOUDS ARE ZOOMING 
THROUGH THE SBA CHANNEL AND WILL AFFECT THE VENTURA COUNTY WEST 
COAST AND THE SBA SOUTH COAST AROUND DAWN. LOW CLOUDS ARE WELL 
ESTABLISHED ACROSS THE CENTRAL COAST AND SANTA YNEZ VLY. AFTERNOON 
GRADIENTS WILL SHOOT UP TO AROUND 7 MB TO KDAG AND THIS WILL CREATE 
SOME GUSTS BETWEEN 30 AND 40 MPH IN THE MTNS AND DESERTS. OF COURSE 
MAX TEMPS WILL BE THE BIG NEWS TODAY WITH MANY LOCATIONS FALLING 15 
DEGREES OR SO. STILL MOST AREAS AWAY FROM THE IMMEDIATE COAST WILL 
BE 5 OR SO DEGREES ABOVE NORMAL.

GOOD ONSHORE FLOW AND TROFING ALOFT WILL BRING LOW CLOUDS TO ALL 
COASTAL AND VLY LOCATIONS TONIGHT. THERE WILL BE A LITTLE SUNDOWNER 
TOWARDS GAVIOTA IN THE EVENING.

MAXIMUM ONSHORE FLOW ON WEDNESDAY WILL ONLY ALLOW THE LOW CLOUDS TO 
RETREAT TO THE COASTS. THE STRONG GRADIENTS WILL ALSO LIKELY CREATE 
ADVISORY LEVEL GUSTS ACROSS THE ANTELOPE VLY. MAX TEMPS WILL TUMBLE 
TO BELOW NORMAL VALUES ACROSS THE AREA DUE TO THE DEEP MARINE LAYER 
AND THE ONSHORE FLOW.

THERE WILL BE CONTINUED TROFING AND ONSHORE FLOW (ALTHOUGH WEAKER 
THAN ON WEDNESDAY) THROUGH FRIDAY AND THIS WILL SERVE AS A HARBINGER 
FOR THE JUNE GLOOM SEASON AS THERE WILL BE NIGHT THROUGH MORNING LOW 
CLOUDS AND SOME FOG.

.LONG TERM (SAT-MON)...
MDLS AGREE THAT A WEAK RIDGE WILL MOVE IN ON SATURDAY AND THIS WILL 
CREATE LESS MARINE LAYER CLOUDS AND A SMALL WARM UP.

FROM THERE ON THERE IS NO AGREEMENT THE EC ADVERTISES TROFING AND 
THE GFS RIDGING. HARD TO PICK SIDES THIS FAR OUT AND OPTED TO PUT IN 
A COASTAL (VLYS CLEAR) MARINE LAYER FORECAST WITH A SLIGHT WARMING 
TREND ESP INLAND. 

&&

.AVIATION...14/1130Z
STRATUS WAS WDSPRD ACROSS THE CENTRAL COAST AND SANTA YNEZ VALLEY
THIS MORNING AND WAS BEGINNING TO DEVELOP ACROSS COASTAL SECTIONS OF 
VTU COUNTY. CLOUDS SHOULD ALSO SPREAD INTO THE L.A. COUNTY COASTAL 
PLAIN AND THE SALINAS VALLEY. CONDS WILL BE MOSTLY LIFR TO IFR THIS 
MORNING. EXPECT SKIES TO CLEAR IN MOST AREAS BY LATE MORNING... 
ALTHOUGH CIGS MAY LINGER NEAR SOME BEACHES INTO THE AFTERNOON. 
EXPECT AN EARLY RETURN OF STRATUS THIS EVENING ACROSS THE COASTAL 
PLAIN...WITH CIGS LIKELY SPREADING INTO MOST VALLEY LOCATIONS BY
MIDNIGHT. NLY GRADS ACROSS SRN SBA COUNTY MAY PRODUCE SOME GUSTY 
WINDS THRU AND BELOW PASSES AND CANYONS THIS EVENING WITH LLWS 
POSSIBLE THIS EVENING NEAR KSBA. NLY GRADS SHOULD ALSO HOLD CLOUDS 
AT BAY ACROSS SRN SBA COUNTY UNTIL LATE TONIGHT. 

14/1140Z

WILL BE ISSUED WITH THE 12Z TAFS

KLAX...LOW TO MODERATE CONFIDENCE IN THE 12Z TAF. THERE IS A 10 TO 
20 PERCENT CHANCE THAT CONDS WILL REMAIN VFR THIS MORNING. THERE IS 
A 20 PERCENT CHANCE THAT IF CIGS ARRIVE THIS MORNING...THEY WILL 
LINGER THROUGH 20Z. THERE IS A 20 PERCENT CHANCE THAT CIGS COULD 
ARRIVE AS EARLY AS 23Z.   

KBUR...MODERATE TO HIGH CONFIDENCE IN THE 12Z TAF. THERE IS A 20 
PERCENT CHANCE THAT CIGS WILL NOT RETURN UNTIL AFTER 09Z.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
GALE WATCH (SEE LAXMWWLOX).

&&



PUBLIC...RORKE
AVIATION...DB
SYNOPSIS...B

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