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000
FXUS66 KLOX 221634
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
935 AM PDT WED MAY 22 2013

.SYNOPSIS...
A COOLING TREND WILL CONTINUE THROUGH THURSDAY...AND THERE WILL BE
PLENTY OF NIGHT THROUGH MORNING LOW CLOUDS AND FOG...ESPECIALLY
ACROSS VENTURA AND LOS ANGELES COUNTIES. THERE MAY BE SOME SLIGHT
WARMING ON FRIDAY...THEN BELOW NORMAL DAYTIME TEMPERATURES ARE
EXPECTED THROUGH THE HOLIDAY WEEKEND WITH NIGHT THROUGH MORNING LOW
CLOUDS AND FOG IN COASTAL AND VALLEY AREAS. WARMING MAY BEGIN ACROSS
THE REGION TUESDAY.

&&

.SHORT TERM (TODAY-FRI)...MARINE LYR UP TO 3500 FT THIS MORNING.
INCREASING NORTHWEST WIND ACROSS THE WESTERN PORTION OF OUR FORECAST
AREA WILL BE BATTLING A SOUTHEAST EDDY WIND ACROSS THE SOUTHEASTERN
PORTION OF OUR FORECAST AREA THE NEXT COUPLE DAYS. SO FAR THIS HAS
RESULTED IN MINIMAL STRATUS FROM SBA COUNTY NORTH AND EARLY CLEARING
ACROSS VENTURA COUNTY. TONIGHT THE EDDY CIRCULATION IS EXPECTED TO
STRENGTHEN AS THE TROF DEEPENS ALONG THE WEST COAST. THIS MAY BE
ENOUGH TO GENERATE SOME PATCHY DRIZZLE, ESPECIALLY ACROSS THE ERN
PORTION OF LA COUNTY WHERE THE EDDY CIRCULATION WILL HAVE ITS
GREATEST INFLUENCE PUSHING UP AGAINST THE SAN GABRIELS.

GUSTY NORTHWEST WINDS EXPECTED ACROSS THE CENTRAL COAST, SRN SBA
COUNTY, I5 CORRIDOR AND THE ANTELOPE VALLEY, ESPECIALLY THIS
AFTERNOON AND EVENING. WINDS EXPECTED TO BE SLIGHTLY WEAKER THURSDAY
INTO THURSDAY EVENING.

COOLER TEMPS AGAIN TODAY WITH THE DEEPER MARINE LYR AND ONSHORE
FLOW. EXCEPT WARMER ACROSS SRN SBA COUNTY DUE TO THE NORTHERLY WINDS
THERE. A FEW MORE DEGREES OF COOLING THU.

***FROM PREVIOUS DISCUSSION***

THE UPPER LOW OVER THE PAC NW LIFTS INTO CANADA THU NIGHT AND
FRI...AND HEIGHTS ACROSS THE FCST AREA WILL BEGIN TO RISE. THIS MAY
ALLOW FOR SOME DECREASE IN MARINE LAYER DEPTH AND A REDUCTION IN
NIGHT THRU MORNING LOW CLOUDS AND FOG W OF THE MTNS. IT SHOULD ALSO
ALLOW FOR A FEW DEGREES OF WARMING ON FRI.

.LONG TERM (SAT-TUE)...ANOTHER UPPER LOW DROPS INTO THE PAC NW FRI
NIGHT AND SAT WITH RENEWED TROFFING ACROSS THE FCST AREA. WITH
DECREASING NW FLOW...EXPECT NIGHT THRU MORNING LOW CLOUDS/FOG TO
BECOME WIDESPREAD IN ALL COASTAL AND MOST VALLEY AREAS. THIS PATTERN
SHOULD CONTINUE THROUGH MONDAY...WITH LOCAL LATE NIGHT AND MORNING
DRIZZLE...AND POTENTIAL SLOW CLEARING NEAR THE BEACHES EACH DAY.
MAX TEMPS WILL LIKELY BE AT LEAST A FEW DEGREES BELOW NORMAL SAT
THRU MON. THE UPPER LOW AND ITS ASSOCD TROUGH WILL MOVE E LATE MON
AND TUE. HEIGHTS/THICKNESS WILL RISE ON TUE...AND SOME WARMING
SHOULD BEGIN.

&&

.FIRE WEATHER...
AS WINDS RAMP UP THIS AFTERNOON AND EVENING ACROSS THE SBA
SOUTH COAST AND MOUNTAINS...I-5 CORRIDOR OF THE LA/VTU COUNTY
MOUNTAINS...AND ANTELOPE VALLEY...THERE WILL BE ELEVATED FIRE DANGER
ACROSS ALL OF THESE AREAS. HUMDITIY LEVELS COULD BRIEFLY FALL BELOW
15 PERCENT ACROSS THE SBA SOUTH COAST ON THIS AFTERNOON.
SIMILAR LOW HUMIDITIES WILL LIKELY IMPACT THE I-5 CORRIDOR AND
ANTELOPE VALLEY DURING THE LATE AFTERNOON AND EVENING HOURS. AS A
RESULT...ALL OF THESE AREAS COULD EXPERIENCE BRIEF CRITICAL FIRE
WEATHER CONDITIONS...ESPECIALLY CONSIDERING THE VERY DRY FUELS FOR
THIS TIME OF YEAR. HOWEVER...IT DOES NOT APPEAR THAT DURATIONS OF
CRITICAL FIRE WEATHER CONDITIONS WILL BE MET TO ISSUE RED FLAG
WARNINGS FOR THIS EVENT.

&&

.AVIATION...22/1120Z...

OVERALL...MODERATE CONFIDENCE IN 12Z TAF PACKAGE. LATEST SATELLITE
SHOWS STRATUS SURGING ACROSS VENTURA/LA COUNTIES...WITH JUST SOME
PATCHY STRATUS ACROSS THE CENTRAL COAST. EXPECT MVFR CIGS ACROSS
VENTURA/LA COASTAL AND VALLEY TAFS THROUGH THE MORNING...WITH SOME
IFR/MVFR CIGS AT KSMX. THE STRATUS SHOULD BURN OFF DECENTLY BY EARLY
THIS AFTERNOON. FOR TONIGHT...EXPECT STRATUS TO RETURN TO THE SAME
SITES AS THIS MORNING WITH SIMILAR MVFR/IFR CIGS.

AS FOR WINDS...THERE WILL BE SOME GUSTY WEST TO NORTHWEST WINDS
ACROSS THE CENTRAL COAST...MOUNTAINS AND ANTELOPE VALLEY THIS
AFTERNOON AND TONIGHT. THE NORTHERLY WINDS WILL BE STRONG ENOUGH
ACROSS SOUTHERN SBA COUNTY TO PRODUCE SOME LLWS/TURBULENCE AT KSBA
THIS EVENING AND OVERNIGHT.

KLAX...MODERATE CONFIDENCE IN 12Z TAF. STRATUS CLEARING TODAY MAY
BE +/- 1-2 HOURS FROM CURRENT 19Z FORECAST.

KBUR...MODERATE CONFIDENCE IN 12Z TAF. STRATUS CLEARING TODAY MAY
BE +/- 1-2 HOURS OF CURRENT 18Z FORECAST.

&&

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

&&

$$

PUBLIC...MW/DB
AVIATION...RAT
FIRE...DG

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