Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 210557
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1040 PM PDT SUN APR 20 2014

.AVIATION DISCUSSION UPDATED...

.SYNOPSIS...
WARM WEATHER WILL CONTINUE INTO MONDAY...EXCEPT FOR SLIGHTLY COOLER
CONDITIONS FOR THE CENTRAL COAST. TEMPERATURES WILL TAKE A TUMBLE
TUESDAY AS LOW PRESSURE BRINGS SOME CLOUDS AND GUSTY WINDS.
TEMPERATURES WILL WARM SLIGHTLY ON WEDNESDAY AND THURSDAY. BY THE
WEEKEND...ANOTHER LOW PRESSURE SYSTEM WILL COOL THINGS DOWN AND
BRING A SLIGHT CHANCE OF SHOWERS TO THE AREA.

&&

.SHORT TERM (TODAY-TUE)...

FORECAST WORKED OUT MOSTLY AS EXPECTED TODAY WITH PLENTY OF SUNSHINE
AND MAX TEMPS 1 TO 3 DEGREES WARMER THAN YDY. BIG EXCEPTION WAS SAN
LUIS OBISPO WHICH HAD ENOUGH A OF A EAST WIND THIS AFTERNOON TO RISE
TEMPS TO 85 DEGREES OR 15 DEGREES WARMER THAN YDY. TOUGH MARINE
LAYER FCST ON TAP FOR TONIGHT WITH CURRENT SATELLITE SHOWING ALMOST
NO LOW CLOUDS. THE NAM DOES SHOW AN EDDY AND LOW CLOUDS DEVELOPING
OVERNIGHT...BUT IT LOOKS LIKE IT INITIALIZED THE LOW LEVEL MOISTURE
FIELD POORLY SO NOT TOO CONFIDENT IN ITS FORECAST. CURRENT FCST IS
REFLECTS THE MAXIMUM POSSIBLE AMOUNT OF LOW CLOUDS BUT THERE WELL
COULD BE MUCH LESS COVERAGE. OTHERWISE FCST IS IN GOOD SHAPE.

FROM THE AFTERNOON DISCUSSION

ON MONDAY...THE CENTRAL COAST SHOULD SEE ABOUT 5 DEGREES OF COOLING
(OR 10 TO 15 AT SLO-TOWN)...AS OFFSHORE FLOW THAT WAS PRESENT
EARLIER TODAY WILL BE WEAKER AND WILL TURN ONSHORE QUICKER AHEAD OF
AN APPROACHING TROUGH. ELSEWHERE...TEMPERATURES WILL REMAIN
SEASONABLY WARM AS 500MB HEIGHTS AND THICKNESS VALUES DON`T CHANGE
MUCH.

MONDAY NIGHT INTO TUESDAY MORNING...A WEAKENING AND MOISTURE STARVED
COLD FRONT ASSOCIATED WITH THE TROUGH WILL MOVE THROUGH THE AREA.
THIS WILL BRING A SLIGHT CHANCE OF SHOWERS TO THE COASTAL AREAS OF
NORTHERN SLO COUNTY...WITH NOTHING MORE THAN AN INCREASE IN MID-HIGH
LEVEL CLOUDS ELSEWHERE. THE TROUGH WILL ALSO BRING MUCH COOLER
WEATHER TO THE AREA ON TUESDAY...WITH THE INLAND AREAS RUNNING 10-15
DEGREES COOLER AND ABOUT 5 DEGREES COOLER AT THE COAST.

FOLLOWING THE PASSAGE OF THE FRONT...MUCH OF THE AREA WILL
EXPERIENCE GUSTY NORTHWEST WINDS TUESDAY AFTERNOON AND EVENING. THE
CENTRAL COAST...SBA SOUTH COAST...MOUNTAINS...AND ANTELOPE VALLEY
MAY END UP NEEDING WIND ADVISORIES DURING THIS PERIOD. THE PASSAGE
OF THE COLD FRONT SHOULD ALSO WIPE OUT THE MARINE LAYER...SO NOT
EXPECTING ANY LOW CLOUDS AND FOG TUESDAY NIGHT AND WEDNESDAY MORNING.

.LONG TERM (WED-SAT)...

LONG RANGE MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH THURSDAY. A
FEW DEGREES OF WARMING IS EXPECTED FOR MOST OF THE AREA ON WEDNESDAY
AND THURSDAY...AS 500MB HEIGHTS RISE A BIT WITH MOSTLY ZONAL FLOW AT
MID-LEVELS. MODELS DISAGREE SOMEWHAT WITH THE STRENGTH OF A TROUGH
APPROACHING THE AREA FOR FRIDAY AND SATURDAY.  THE GFS AND GEM HAVE
BEEN STRONGER AND WETTER WITH THIS SYSTEM...WHILE THE ECMWF HAS BEEN
MOSTLY DRY...ALTHOUGH THE 12Z RUN OF THE ECMWF DID COME IN A BIT
WETTER. FOR THIS REASON A SLIGHT CHANCE POPS WERE ADDED TO MOST OF
THE AREA FRIDAY NIGHT INTO SATURDAY.

&&

.AVIATION...21/06Z...
MODERATE TO HIGH CONFIDENCE IN THE 06Z TAFS WITH THE REDUCED
CONFIDENCE DUE TO UNCERTAINTY IN THE TIMING... INTENSITY... AND
LOCATION OF PATCHY COASTAL LOW CLOUDS AND FOG.  AT KLGB 10Z-17Z AN
80 PERCENT CHANCE OF MVFR CONDITIONS AND 60 PERCENT CHANCE OF IFR.
AT KLAX 12Z-17Z A 70 PERCENT CHANCE OF MVFR CONDITIONS AND A 55
PERCENT CHANCE OF IFR CONDITIONS.  NORTH OF POINT CONCEPTION AN 80
PERCENT CHANCE OF MVFR CONDITIONS AND A 50 PERCENT CHANCE OF
VLIFR/LIFR CONDITIONS ESPECIALLY AT KSMX.  OTHERWISE AND ELSEWHERE
VFR CONDITIONS ARE EXPECTED.

KLAX...MODERATE TO HIGH CONFIDENCE IN THE 06Z TAF WITH THE REDUCED
CONFIDENCE DUE TO UNCERTAINTY IN THE TIMING... INTENSITY... AND
LOCATION OF PATCHY COASTAL LOW CLOUDS AND FOG.  FROM 12Z-17Z A 70
PERCENT CHANCE OF MVFR CONDITIONS AND A 55 PERCENT CHANCE OF IFR
CONDITIONS.  OTHERWISE VFR CONDITIONS ARE EXPECTED.

KBUR...HIGH CONFIDENCE IN THE 06Z TAF.  A FIVE PERCENT CHANCE OF
MVFR VSBYS 12Z-18Z... OTHERWISE VFR CONDITIONS ARE EXPECTED
THROUGHOUT THE FORECAST PERIOD.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&
$$

PUBLIC...SUKUP/ASR
AVIATION...KJ
SYNOPSIS...SWEET

WWW.WEATHER.GOV/LOSANGELES






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