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000
FXUS66 KLOX 232107
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
205 PM PDT THU MAY 23 2013

.SYNOPSIS...

GUSTY NORTHWEST WINDS WILL CONTINUE TONIGHT ACROSS THE
MOUNTAINS...DESERTS...AND PORTIONS OF THE CENTRAL COAST. LOW
PRESSURE WILL LINGER OVER THE WESTERN UNITED STATES THROUGH EARLY
NEXT WEEK WITH AREAS OF NIGHT THROUGH MORNING LOW CLOUDS AND FOG.
TEMPERATURES WILL STAY BELOW NORMAL THROUGH EARLY NEXT WEEK...THEN A
WARMING TREND SHOULD BEGIN BY MIDWEEK AS LOW PRESSURE MOVES EAST.

&&

.SHORT TERM (TONIGHT-SUN)...
STRATOCUMULUS HAS HUNG IN THERE ALL DAY ACROSS AREAS OF VENTURA AND
LOS ANGELES COUNTIES...AND LITTLE CHANGE HAS OCCURRED WITH THE
MARINE INVERSION TODAY. AFTERNOON HIGHS STAYED THE COURSE OF MANY
DEGREES COOLER THAN YESTERDAY IN MOST AREAS. WINDS INCREASED ALONG
THE CENTRAL COAST...MOUNTAINS...AND ANTELOPE VALLEY THIS AFTERNOON.
ONSHORE PRESSURE GRADS ARE NOT AS STRONG AS YESTERDAY AND SPEEDS ARE
REFLECTING THIS. EXPECT LOW-END WIND ADVISORIES TO CONTINUE INTO THE
EVENING/NIGHT AS PLANNED.

MARINE INVERSION REMAINS ABOVE 4K FEET THIS AFTERNOON. MODEL 30AGL
HUMIDITY SHOWS LOW CLOUDS REFORMING IN A SIMILAR FASHION AS LAST
NIGHT ACROSS VENTURA AND LOS ANGELES COUNTIES...ALTHOUGH THE EDDY IS
NOT AS ROBUST BY FRIDAY MORNING SO THERE COULD BE A LITTLE MORE
RAGGED LOOK TO THE CLOUD DECK. ALONG THE CENTRAL COAST WINDS TURN
SLIGHTLY OFFSHORE SO DON`T EXPECT CLOUDS TO FORM OVERNIGHT.

VERY LITTLE CHANGES FOR THE WEEKEND. THE LOW PRESSURE SYSTEM OVER
THE PACIFIC NORTHWEST REMAINS STATIONARY WITH HEIGHTS REMAINING
STATIC OVER SOUTHERN CA THROUGH SUNDAY. TEMPERATURES WILL BE A
COUPLE OF DEGREES HIGHER THAN TODAY BUT THAT`S ABOUT IT. NIGHT AND
MORNING LOW CLOUDS AND PATCHY FOG SHOULD RETURN ALONG THE SOUTH
COAST AND REORGANIZE ALONG THE CENTRAL COAST OVER THE WEEKEND.

.LONG TERM (MON-THU)...
THE LONG RANGE BECOMES A LITTLE MORE FUZZY WITH LOWER FORECAST
CONFIDENCE FOR MONDAY AND TUESDAY. WITH THE PAC NORTHWEST LOW
PRESSURE SYSTEM STALLING OUT...THIS ALLOWS TIME FOR A STRONGER
NORTHWEST JET STREAM TO REACH THE EASTERN PAC AND DIG DOWN THE
BACKSIDE OF THE LOW PRESSURE TROUGH. BY TUESDAY MORNING THIS JET
STREAM IS RAPIDLY PUSHING 90+KTS ALONG THE CENTRAL COAST AS THE
TROUGH AMPLIFIES ACROSS THE GREAT BASIN. THE ECMWF HAS BEEN THE MOST
AGGRESSIVE FOR THE PAST TWO RUNS...BUT THE GFS IS ALSO SHOWING
ENOUGH TO WARRANT A SLIGHT CHANCE OF SHOWERS LATE MONDAY NIGHT
THROUGH TUESDAY EVENING. GUSTY NORTHWEST WINDS MAY TURN OUT TO THE
BIGGER STORY FOR THE CENTRAL COAST...MOUNTAINS...AND AV DURING THIS
TIME FRAME. THE TROUGH LOOKS PROGRESSIVE AND SHOULD CLEAR SOUTHERN
CA BY WEDNESDAY BUT IT MAY REMAIN RATHER WINDY IN PLACES. EXPECT
TEMPERATURES TO BE BELOW NORMAL EARLY IN THE WEEK THEN WARMING AS A
RIDGE BUILDS IN MID-WEEK.

&&

.AVIATION...23/1800Z.
PERSISTENCE FORECAST WILL KEEP A DEEP AND RATHER WEAK MARINE LAYER
OVER THE AREA. MVFR TO VFR CIGS OVER KOXR AND THE LA COAST AND
VALLEY SITES WILL DISSIPATE FROM 18Z-20Z TODAY...ALTHOUGH TIMING MAY
DIFFER BY +/- 1 HR.

N OF PT CONCEPTION THERE IS A 20% CHANCE THAT MVFR CIGS WILL AFFECT
KSMX OVERNIGHT.

S OF PT CONCEPTION EXPECT MVFR CIGS TO REFORM OVER KOXR AND LA COAST
AND VALLEY SITES...BUT THE TIMING MAY DIFFER +/- 2 HRS FROM TAF
TIMES. 10% CHANCE THAT ANY OF THESE SITES WILL SEE VFR CIGS FORM
OVERNIGHT...OR THAT ONLY SCATTERED LOWER CLOUDS WILL DEVELOP.

PERIODS OF MODERATE TO OCCASIONALLY STRONG LOW-LEVEL WIND SHEAR AND
TURBULENCE IS POSSIBLE AT KSBA AFTER 23Z.

KLAX...MODERATE TO HIGH CONFIDENCE IN 18Z TAFS. BROKEN VFR CIGS WILL
SCATTER OUT THROUGH 20Z. MVFR CIGS WILL RETURN BY 08Z...WITH A 30%
CHANCE THAT TIMING WILL DIFFER +/- 2 HRS FROM TAF TIMES. THERE IS A
10% CHANCE CONDS WILL REMAIN VFR OVERNIGHT.

KBUR...MODERATE CONFIDENCE IN 18Z TAFS. BROKEN VFR CIGS WILL SCATTER
OUT THROUGH 22Z. THERE IS A 30% CHANCE THAT VFR CONDS WILL CONTINUE
THROUGH THE OVERNIGHT PERIOD. OTHERWISE MVFR CIGS ARE EXPECTED AFTER
09Z...BUT TIMING COULD DIFFER +/- 2 HRS FROM TAF TIMES.

&&

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

&&

$$

PUBLIC...BOLDT
AVIATION...SMITH
SYNOPSIS...SUKUP

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