Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 220005
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
505 PM PDT TUE OCT 21 2014

.SYNOPSIS...

HIGH PRESSURE WILL BUILD OVER THE AREA TO BRING A SLIGHT WARMING
TREND THROUGH FRIDAY. AN UPPER LEVEL TROUGH THEN SLIDES THROUGH THE
AREA OVER THE WEEKEND FOR COOLER TEMPERATURES AND POSSIBLY SOME
LIGHT PRECIPITATION NORTH OF POINT CONCEPTION...MAINLY ON SATURDAY.

&&

.SHORT TERM (WED-FRI)...OTHER THAN SOME HIGH CLOUDS CRUISING THROUGH
IN NORTHWESTERLY FLOW...A PRETTY QUIET AFTERNOON ACROSS THE AREA SO
FAR. HEIGHTS HAVE BEGUN TO RISE IN ADVANCE OF SOME BUILDING WEAK
HIGH PRESSURE THAT WILL HELP WARM THINGS THROUGH THE WEEK. SOME OF
THAT WARMING HAS STARTED TODAY ALONG COASTAL AREAS WHILE THE
MOUNTAINS AND DESERTS HAVE ACTUALLY COOLED A FEW DEGREES FROM
YESTERDAY. MAIN FORECAST ISSUE IN THE NEAR TERM WILL BE SUNDOWNER
WINDS THAT SHOULD DEVELOP ONCE AGAIN THIS EVENING OVER THE SANTA
BARBARA SOUTH COAST. NORTH TO SOUTH PRESSURE GRADIENTS ACROSS THE
SOUTH COAST ARE SIMILAR TO LAST NIGHT`S WHEN SOME OF THE HIGHER
AREAS OF MONTECITO EXPERIENCED WIND GUSTS JUST OVER 40 MPH. MODEL
CROSS SECTIONS ARE ALSO VERY SIMILAR FOR TONIGHT SO WIND ADVISORY IS
IN ORDER FOR THE AREA FOR SIMILAR WINDS THAT COULD GUST AS HIGH AS
THE LOW 40S IN THE USUAL SPOTS...DIMINISHING BY SUNRISE. GRADIENTS
WEAKEN TOMORROW NIGHT SO AT THIS TIME NOT EXPECTING WINDS TO RETURN
WED NIGHT.

OTHERWISE...THROUGH FRIDAY...HIGH PRESSURE WILL CONTINUE TO BUILD
OVER THE SOUTHWEST UNITED STATES TO HELP GRADUALLY WARM TEMPERATURES
THROUGH THE WEEK. THURSDAY AND FRIDAY ARE BOTH PRETTY SIMILAR AS FAR
AS HIGH TEMPERATURES GO...SOME SPOTS WARMER FRIDAY...SOME SPOTS A
DEGREE OR TWO COOLER. GENERALLY EXPECT HIGHS TO BE 5 TO 10 DEGREES
ABOVE NORMAL BOTH DAYS.

.LONG TERM (SAT-TUE)...
BY SATURDAY MODELS ARE NOW ALL IN PRETTY GOOD AGREEMENT WITH PLACING
A DIGGING TROUGH JUST OFF THE WEST COAST...AND AT THIS POINT
SWINGING ITS MAIN AXIS THROUGH THE AREA LATE ON SATURDAY. 12Z
GUIDANCE PUSHES A WEAK FRONT THROUGH DURING THE DAY ON
SATURDAY...AND ALTHOUGH MODELS DO PRODUCE SOME LOW POPS OVER AREAS
NORTH OF POINT CONCEPTION ON SATURDAY...FRONT APPEARS PRETTY WEAK
THIS FAR SOUTH WITH BEST QPF WELL NORTH OF OUR AREA INTO NORTHERN
CALIFORNIA. LEFT CURRENT FORECAST OF SLIGHT CHANCE POPS NORTH OF
POINT CONCEPTION AS IS FOR SATURDAY. AT THIS TIME DON`T EXPECT ANY
MEASURABLE PRECIP SOUTH OF THE POINT WITH THIS SYSTEM...ESPECIALLY
GIVEN THE LATEST 12Z ECMWF HAS BACKED OFF ON THE TROF`S INTENSITY
FROM ITS PREVIOUS RUN.

THE PASSING TROUGH WILL HELP DROP TEMPERATURES ACROSS THE AREA ON
SATURDAY AND SUNDAY...WITH HIGHS 10 TO IN SOME PLACES 15 OR SO
DEGREES COOLER THAN HIGHS ON FRIDAY AND PLENTY BELOW
NORMAL...HELPING IT FEEL VERY FALL LIKE. TROUGH AND ASSOCIATED FRONT
WILL ALSO BRING SOME GUSTY NORTHERLY WINDS THROUGH PASSES AND
CANYONS.

SOME VERY MINOR DIFFERENCES BETWEEN GFS AND EC PAST SUNDAY AS FAR AS
THE BRINGING HIGH PRESSURE IN BEHIND SATURDAY`S TROUGH. BUT IN
GENERAL RISING HEIGHTS WILL WARM AFTERNOON TEMPERATURES A FEW
DEGREES EACH DAY ON MONDAY AND TUESDAY. OFFSHORE FLOW WILL BE
STRONGEST ON MONDAY ALTHOUGH NOT MUCH TO SPEAK OF.

&&

.AVIATION...22/0000Z.

THE MARINE LAYER AT KLAX AT 2350Z WAS 1200 FEET DEEP AND THE
INVERSION TOP IS AT 1900 FEET WITH A TEMPERATURE OF 20 DEGREES C.

N OF POINT CONCEPTION...HIGH CONFIDENCE FOR VFR CONDS OVER NEXT 24
HOURS. 20 PERCENT CHANCE FOR IFR VSBYS/CIGS 09Z-15Z TONIGHT INTO WED
MORNING. 30 PERCENT CHANCE FOR IFR CIGS AT KPRB AFTER 10Z THROUGH
16Z.

S OF POINT CONCEPTION...

HIGH CONFIDENCE FOR VFR CONDS ALL INLAND TAFS SITES AND SBA/VTA
COUNTY TAFS. 50 PERCENT CHANCE FOR IFR CIGS FOR KLGB AND KLAX AFTER
09Z-16Z.

KLAX...HIGH CONFIDENCE IN THE 00Z TAF THROUGH 06Z..THEN LOWER
CONFIDENCE TO 50 PERCENT FOR IFR CIGS AFTER 10Z THROUGH 16Z.
OTHERWISE EXPECT VFR CONDS.

KBUR...GOOD CONFIDENCE IN THE 00Z TAF. THERE IS A 20 PERCENT CHANCE
OF BRIEF IFR CONDITIONS LATE TONIGHT AND EARLY WEDNESDAY.

&&

.MARINE...21/200 PM...
GOOD CONFIDENCE IN GALE FORCE WINDS THROUGH LATE TONIGHT ACROSS THE
OUTER WATERS. REASONABLY GOOD CONFIDENCE THAT CONDS ACROSS THE
NORTHERN THIRD OF THE OUTER WATERS WILL INCREASE TO GALE LEVEL THIS
AFTERNOON...THEN CONT THROUGH LATE TONIGHT. GOOD CONFIDENCE IN SCA
CONDITIONS ACROSS THE NRN INNER WATERS THROUGH LATE TONIGHT...FOR
MAINLY SEAS THIS MORNING...THEN WINDS AND SEAS THROUGH LATE TONIGHT.
THERE IS A 60 PERCENT CHANCE OF SC WINDS ACROSS WESTERN PORTIONS OF
THE SBA CHANNEL LATE THIS AFTERNOON AND EVENING.

LARGE AND FAIRLY LONG PERIOD COMBINED SEAS OF 10 TO 15 FEET ACROSS
THE OUTER WATERS...AND 9 TO 12 FEET ACROSS THE NORTHERN INNER
WATERS SHOULD BEGIN TO SUBSIDE TONIGHT.


&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY (SEE LAXNPWLOX).
GALE WARNING (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&
$$

PUBLIC...JACKSON
AVIATION/MARINE...SWEET
SYNOPSIS...JACKSON/KH

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