Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 250428 CCA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
913 PM PDT SUN MAY 24 2015

.SYNOPSIS...A PERSISTENT UPPER LEVEL TROUGH OVER THE WESTERN UNITED
STATES WILL MAINTAIN NEAR BELOW NORMAL TEMPERATURES THROUGH MID WEEK
WITH AMPLE NIGHT THROUGH MORNING CLOUDS. AN AMPLIFIED RIDGE OF HIGH
PRESSURE WILL BUILD OVER CALIFORNIA THURSDAY THROUGH NEXT WEEKEND
BRINGING A SHARP WARMING TREND AWAY FROM THE COAST. COASTAL AREAS
SHOULD CONTINUE TO SEE LOW CLOUDS AND FOG...AND HIGH TEMPERATURES
WHICH WILL MODERATE UP A BIT.

&&

.UPDATE...

WESTERLY FLOW ALOFT WILL KEEP AN ONSHORE FLOW IN PLACE THROUGH THE
WEEK AND COOLER THAN NORMAL CONDITIONS INTO LATE WEEK. A WEAK
NORTHERLY SURFACE PRESSURE GRADIENT WILL CONTINUE THROUGH MEMORIAL
DAY...ALLOWING FOR LOCALLY BREEZY WINDS THROUGH THE INTERSTATE 5
CORRIDOR AND ACROSS SOUTHERN SANTA BARBARA COUNTY.

A DEEP MARINE LAYER IS IN PLACE ON THE LATEST AMDAR SOUNDINGS AT
KLAX. KLAX AMDAR SOUNDINGS INDICATE A MARINE LAYER DEPTH AROUND 2700
FEET THIS EVENING...BUT IT IS BECOMING SHALLOWER FROM NORTH TO
SOUTH. THUS...THE MARINE LAYER DEPTH IS MUCH SHALLOWER NORTH OF
POINT CONCEPTION...PROBABLY CLOSER TO 2000 FEET. STRATUS IS ALREADY
SPREADING INTO THE CENTRAL COAST THIS EVENING AND IT SHOULD BECOME
MORE WIDESPREAD LATER TONIGHT AS THE MARINE INVERSION SHOULD
STRENGTHEN SOMEWHAT TONIGHT. SOUTH OF POINT CONCEPTION...AN EDDY
CIRCULATION WILL REGENERATE LATE TONIGHT WHICH SHOULD ALLOWING FOR
STRATUS CLOUDS TO SPREAD BACK IN AGAIN.

THE CURRENT PACKAGE LOOKS AGREEABLE FOR TEMPERATURES AND STRATUS
COVERAGE AND NO UPDATES ARE PLANNED.

&&

.PREV DISCUSSION...

SHORT TERM...NOT A WHOLE LOT OF CHANGES THROUGH WEDNESDAY. THE
MARINE LAYER AND ASSOCIATE STRATUS SHOULD CHANGE VERY LITTLE IN THE
BIG PICTURE...BUT THERE WILL BE RANDOM UNEXPECTED VARIATIONS WHICH
WILL AFFECT TEMPERATURES PLUS OR MINUS A FEW DEGREES. THE ONLY
CHANGE WORTH NOTING IS FOR SOME EXTRA HIGH CLOUDS IN THE AREA ON
TUESDAY AND WEDNESDAY.

LONG TERM...A RIDGE OF HIGH PRESSURE PATIENTLY WAITING TO THE WEST
SHOULD HAVE AN OPPORTUNITY TO SHIFT OVER CALIFORNIA ON THURSDAY OR
FRIDAY...THEN ENVELOPE THE WESTERN UNITED STATES OVER NEXT WEEKEND.
THIS WILL BRING A HEALTHY WARMING TREND...WITH TEMPERATURES GOING 5
TO 10 DEGREES ABOVE NORMAL AWAY FROM THE COAST BY FRIDAY OR
SATURDAY. THE COASTAL AREAS SHOULD CONTINUE TO SEE MORNING LOW
CLOUDS AND FOG...WHICH COULD BE MORE STUBBORN AND SOLID THAN WHAT WE
ARE SEEING NOW THANKS TO A LIKELY STRONG INVERSION. THIS SHOULD KEEP
THE COASTAL SECTION MOSTLY FREE FROM THE WARMING TREND...AND
MODERATE SOME OF THE WARMING OVER THE COASTAL VALLEY AREAS.

&&

.AVIATION...25/0000Z.

AT 0000Z...THE MARINE LAYER DEPTH AT KLAX WAS AROUND 3200 FT DEEP.
THE TOP OF THE INVERSION WAS NEAR 5900 FEET WITH A TEMPERATURE OF 11
DEGREES CELSIUS.

MODERATE CONFIDENCE IN THE CURRENT FORECAST. HIGHEST CONFIDENCE
EXISTS IN MVFR CONDITIONS FOR LOS ANGELES COUNTY TERMINALS AND
TERMINALS NORTH OF POINT CONCEPTION. THERE IS A CHANCE THAT THE
TIMING COULD BE UP TO TWO HOURS EARLIER. THERE IS A CHANCE OF IFR
CONDITIONS AT TERMINALS NORTH OF POINT CONCEPTION...MAINLY BETWEEN
08Z AND 16Z..

KLAX...MODERATE CONFIDENCE IN THE CURRENT FORECAST. MVFR CONDITIONS
WILL SPREAD IN BETWEEN 04Z AND 08Z. THERE IS A 30 PERCENT CHANCE
THAT VFR CONDITIONS COULD DEVELOP AS SOON AS 17Z. THERE IS A 20
PERCENT CHANCE OF SOUTHEAST WINDS GREATER THAN 10Z BETWEEN 13Z AND
16Z.

KBUR...MODERATE CONFIDENCE IN THE CURRENT FORECAST. MVFR CONDITIONS
WILL SPREAD IN BETWEEN 06Z AND 10Z. THERE IS A 30 PERCENT CHANCE
THAT VFR CONDITIONS COULD DEVELOP AS SOON AS 15Z.

&&

.MARINE...24/900 PM.

SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE ACROSS THE OUTER
WATERS THROUGH LATE TONIGHT. LOCAL SMALL CRAFT ADVISORY WINDS MAY
OCCUR ACROSS THE WESTERN PORTION OF THE SANTA BARBARA CHANNEL AND
THE NEARSHORE WATERS BETWEEN POINT PIEDRAS BLANCAS AND POINT SAL.
THERE IS A 20 PERCENT CHANCE THAT SMALL CRAFT ADVISORY CONDITIONS
COULD LINGER UNTIL 9 AM PDT MONDAY FOR THE SOUTHERN OUTER WATERS.

WINDS SHOULD WEAKEN BY 9 AM PDT MONDAY AT THE LATEST...BUT THERE IS
A CHANCE OF SMALL CRAFT ADVISORY CONDITIONS FOR THE SOUTHERN OUTER
WATERS TUESDAY AFTERNOON AND NIGHT.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
BEACH HAZARDS STATEMENT (SEE LAXCFWLOX).

&&

$$

PUBLIC...HALL/KITTELL
AVIATION...HALL
MARINE...HALL
SYNOPSIS...KAPLAN

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