FXUS66 KLOX 252117
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
215 PM PDT SAT MAY 25 2013
.SYNOPSIS...
LOW PRESSURE TO THE NORTH WILL RESULT SLIGHTLY BELOW NORMAL 
TEMPERATURES THROUGH EARLY NEXT WEEK...ALONG WITH NIGHT THROUGH 
MORNING LOW CLOUDS AND PATCHY FOG FOR THE COASTAL PLAIN AND VALLEYS. 
A TROUGH OF LOW PRESSURE WILL MOVE THROUGH THE AREA MONDAY NIGHT AND 
TUESDAY...BRINGING A CHANCE OF SHOWERS AS WELL AS GUSTY NORTH TO 
NORTHWEST WINDS. A WARMING TREND IS THEN EXPECTED LATE NEXT WEEK.
&&
.SHORT TERM (TONIGHT-TUE)...MAIN CONCERNS IN THE FORECAST ARE THE 
ANTICIPATED WINDS AND LIGHT SHOWERS. UPPER LEVEL TROUGH REMAINS 
PARKED ACROSS THE PACIFIC NORTHWEST WITH LITTLE CHANGE IN CONDITIONS 
FOR SOUTHERN CAL TODAY. TEMPERATURES REMAINED SIMILAR TO YESTERDAY 
OR A FEW DEGREES COOLER. OCCASIONAL WIND GUSTS OVER 35 MPH ACROSS 
THE WESTERN AV BUT NOTHING OUT OF THE ORDINARY TODAY. 
HEIGHTS GO UP SLIGHTLY ON SUNDAY SO THERE WILL BE SOME WARMING FOR 
INLAND AREAS. LOW CLOUDS SHOULD PLAGUE THE COASTAL REGIONS SUNDAY 
MORNING AND MAY ONLY BURN OFF TO THE BEACHES IN THE AFTERNOON. CLOUD 
COVER WILL HOLD DOWN TEMPERATURES FOR THESE AREAS. WEST TO SOUTHWEST 
WINDS WILL INCREASE AND BECOME MORE WIDESPREAD ACROSS THE AV SUNDAY 
AFTERNOON AND CONTINUE INTO SUNDAY NIGHT. THIS IS MAINLY DUE TO A 
TIGHTER PRESSURE GRADIENT AND BUMP UP IN UPPER LEVEL WINDS TOMORROW. 
OFFSHORE FLOW DEVELOPS FOR SOUTHERN SANTA BARBARA COUNTY SUNDAY 
NIGHT SO A WEAK SUNDOWNER IS EXPECTED FOR WESTERN SECTIONS NEAR 
CANYON MOUTHS. 
ON MONDAY...A STRONGER LOW PRESSURE SYSTEM DROPS INTO THE PACIFIC 
NORTHWEST ACCOMPANIED BY A 100+KT NORTHWESTERLY JET. CLOUDS WILL 
START TO INCREASE ACROSS ALL AREAS MONDAY AFTERNOON AND WINDS WILL 
BECOME GUSTY FOR MANY AREAS...ESPECIALLY THE MOUNTAINS AND DESERTS. 
WOULD EXPECT SOLID WIND ADVISORIES FOR THESE AREAS ON MONDAY AND 
TUESDAY. THE FRONT ASSOCIATED WITH THIS SYSTEM WEAKENS AS IT 
APPROACHES THE CENTRAL COAST MONDAY NIGHT/TUESDAY MORNING...BUT WILL 
CONTINUE WITH A CHANCE OF SHOWERS NORTH OF PT CONCEPTION. THE OTHER 
AREAS WITH THE HIGHEST RISK OF SHOWERS WILL BE THE NORTH SLOPE OF 
THE MOUNTAINS. IT WILL BE HARD TO GET MUCH OF ANYTHING RAIN-WISE FOR 
THE SOUTH COASTAL SLOPES AND COASTS OF VENTURA AND LOS ANGELES 
COUNTIES DUE TO THE STRONG NORTHWEST FLOW. WOULD EXPECT DECREASING 
CLOUD COVER IN THE WAKE OF THIS SYSTEM BY TUESDAY AFTERNOON. 
.LONG TERM (WED-SAT)...CONTINUING WINDY CONDITIONS ON WEDNESDAY BUT 
REMOVED ANY MENTION OF SHOWERS BY THEN. TEMPERATURES WILL REMAIN 
BELOW NORMAL ON WEDNESDAY. A HIGH PRESSURE RIDGE WILL BUILD INTO THE 
WEST COAST STARTING THURSDAY AND LINGER THROUGH SATURDAY. A DRY 
OFFSHORE FLOW WILL SQUASH ANY LOW CLOUD DEVELOPMENT AND EXPECT 
TEMPERATURES TO PUSH WELL INTO THE 80S AND 90S LATE IN THE WEEK FOR 
INLAND VALLEYS. THE ECMWF MODEL HINTS AT SOME BACKBUILDING OF THE 
CENTRAL STATES TROUGH BY SATURDAY WHICH WOULD DROP HEIGHTS 
SOME...BUT GFS STAYS MORE PROGRESSIVE AND ON THE WARMER SIDE. 
&&
.AVIATION...25/1800Z...
MODERATE CONFIDENCE IN 18Z TAFS...WITH A DEEP MARINE LAYER EXPECTED 
TO BRING SOMEWHAT MORE WIDESPREAD STRATUS CLOUDS TO THE COAST AND 
VALLEYS OVERNIGHT INTO SUNDAY MORNING. EXPECT KSBA TO REMAIN CLEAR 
OVERNIGHT...BUT THERE IS A 10% CHANCE OF IFR CIGS FORMING OVERNIGHT. 
EXPECT IFR/MVFR CIGS TO FORM OVERNIGHT FOR THE CENTRAL COAST SITES 
AND KPRB...ALTHOUGH LOWER CONFIDENCE IN THE TIMING AND HEIGHT OF LOW 
CLOUDS FOR KPRB. 
S OF PT CONCEPTION...EXPECT FAIRLY SIMILAR MARINE LAYER DEPTH AND 
COVERAGE...BUT PUSHING FURTHER NORTH ALONG THE VENTURA COAST TO 
KOXR. THE TIMING OF STRATUS CLOUDS ARRIVING AT THE AIRFIELDS MAY 
DIFFER UP TO 2 HRS FROM TAF TIMES. 
KLAX...MODERATE TO HIGH CONFIDENCE IN 18Z TAF. THE MODERATE 
CONFIDENCE IS FOR TIMING OF STRATUS RETURN TONIGHT...WHICH MAY 
DIFFER UP TO 2 HRS FROM TAF TIME OF 07Z. 
KBUR...MODERATE CONFIDENCE IN 18Z TAF. THE TIMING OF MVFR CIGS 
SCATTERING OUT THIS AFTERNOON IS UNCERTAIN... AND THE TIMING OF 
STRATUS RETURN TONIGHT IS LOWER CONFIDENCE. 
$$ 
.LOX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
GALE WATCH (SEE LAXMWWLOX).
&&
$$
PUBLIC...BOLDT
AVIATION...SMITH
SYNOPSIS...SUKUP
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