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000
FXUS66 KLOX 132101 CCA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
155 PM PDT THU JUN 13 2013

.SYNOPSIS...

A SLIGHT TEMPERATURE WARMUP ON FRIDAY AS HIGH PRESSURE DEVELOPS.
TYPICAL NIGHT THROUGH MORNING CLOUDS AND FOG FOR COAST AND VALLEYS
EXPECTED THROUGH NEXT WEEK WITH TEMPERATURES NEAR NORMAL.

&&

.SHORT TERM (TODAY-SUN)...SURFACE HIGH PRESSURE BUILDING TO THE
NORTH DOING A GOOD JOB OF CLEARING THE MARINE LYR DOWN TO VENTURA
COUNTY THIS AFTERNOON. STILL HOLDING ON TIGHT ALONG THE LA/VTA COAST
TODAY BUT CLEAR ELSEWHERE. THE NORTHERLY PUSH WILL GENERATE SOME
GUSTY SUB-ADVISORY LEVEL WINDS BELOW THE SANTA YNEZ RANGE AND
THROUGH THE I5 CORRIDOR THIS EVENING AND SHOULD KEEP PUSHING THE
STRATUS FIELD SOUTH AND EAST. THEN OVERNIGHT EXPECT THE CLOUDS TO
RETURN NORTH AND MOVE AS FAR NORTH AS SBA BY MID MORNING FRIDAY.
INLAND PUSH TONIGHT SHOULD BE LESS AS ONSHORE FLOW IS WEAKER AND
INVERSION SHRINKS.

NOT EXPECTING MUCH IN THE WAY OF NORTHEAST WINDS FRIDAY BUT SHOULD
SEE EARLIER CLEARING FOR COASTAL AREAS AND HIGHS UP 2-4 DEGREES ON
AVERAGE. A LITTLE BETTER WARMING FOR THE CENTRAL COAST DUE TO
SLIGHTLY STRONGER NORTHEAST FLOW AND CLEAR SKIES.

BIG REVERSAL IN CONDITIONS SATURDAY AS A TROF DEEPENS ALONG THE
COAST. THIS WILL DEEPEN THE MARINE LYR AND STRENGTHEN THE ONSHORE
FLOW, PUSHING LOW CLOUDS UP THE COAST AND WELL INTO THE VALLEYS BY
SAT MORNING. HIGH TEMPS WILL BE DOWN 5-10 DEGREES WITH THE LARGEST
DROPS IN THE COASTAL VALLEYS.

THE TROF LIFTS SLIGHTLY SUNDAY BRINGING SMALL HEIGHT RISES ACROSS
THE AREA. SO SLIGHTLY EARLIER CLEARING AND A COUPLE DEGREES OF
WARMING, MAINLY INLAND.

.LONG TERM (MON-THU)...EXCITEMENT FACTOR EXTREMELY LOW NEXT WEEK.
MODELS NOT REALLY IN GREAT AGREEMENT BUT NONE OF THEM OFFER ANYTHING
MORE THAN FAIRLY TYPICAL JUNE CONDITIONS. THE GFS SUGGESTS MORE
WARMING THROUGH MID WEEK WHILE THE ECMWF IS COOLER BUT NO EXTREMES
EITHER WAY.

&&

.AVIATION...13/18Z...
DIFFICULT TO BE TOO CONFIDENT WITH THE TIMING AND EXTENT OF THE
MARINE LAYER FOR THE NEXT 24 TO 36 HOURS AS A WEAK TROUGH MOVES
THROUGH THE REGION AND MILD OFFSHORE FLOW DEVELOPS.  ALONG THE
CENTRAL COAST... INLAND LOCATIONS WERE SLOW TO DEVELOP CIGS AND POOR
VSBYS AND LITTLE MARINE LAYER EXISTED IN OPEN WATER.  THIS SCOURING
SHOULD BE AS PRONOUNCED AND PERHAPS A BIT MORE TONIGHT.
NORTHEASTERLY WINDS WILL BE STRONGEST IN THE EVENING SO CENTRAL
COAST SITES WILL MOST LIKELY DEVELOP CIGS AND LOWERED VSBYS WITHIN A
FEW HOURS OF DAYBREAK.  SOUTH OF PT CONCEPTION... GOOD PENETRATION
OF LOW CLOUDS AND FOG THIS MORNING BUT THIS IS NOT EXPECTED TO
REPEAT TONIGHT DUE TO THE NORTHERLY FLOW AND SWITCH TO AN OFFSHORE
FLOW.  THE MARINE LAYER SHOULD BE THINNER... LATER TO FORM AND
EARLIER TO DIMINISH ON FRIDAY.  ANTELOPE VALLEY LOCATIONS WILL BE
GUSTY TODAY THROUGH FRIDAY MORNING BUT VFR CONDITIONS WILL PREVAIL.

KLAX...LOW TO MODERATE CONFIDENCE IN THE 18Z TAF DUE TO UNCERTAINTY
IN TIMING AND EXTENT OF DEVELOPMENT OF LOW CLOUDS AND FOG.  THE
IFR/MVFR CONDITIONS ARE EXPECTED TO DEVELOP BUT LATER... DIMINISHING
EARLIER... AND NOT AS DEEP.

KBUR...MODERATE CONFIDENCE IN THE 18Z TAF. SOME PENETRATION OF THE
MARINE LAYER IS EXPECTED INTO THE SAN FERNANDO VALLEY BUT ANY
IFR/MVFR CONDITIONS WILL BE WITHIN A FEW HOURS OF DAYBREAK AND
OTHERWISE VFR CONDITIONS WILL PREVAIL.

&&

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

&&

$$

PUBLIC...MW
AVIATION...KJ

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