Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 171744 AAB
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
940 AM PDT THU APR 17 2014

UPDATED AVIATION DISCUSSION

.SYNOPSIS...

ONSHORE FLOW WILL CONTINUE TO BRING COOL TEMPERATURES TO THE AREA
THROUGH FRIDAY WITH PARTLY TO MOSTLY CLOUDY SKIES. MORNING
DRIZZLE IS POSSIBLE AT COASTS AND VALLEYS FRIDAY MORNING. EXPECT
WARMER WEATHER OVER THE WEEKEND INTO MONDAY BEFORE A TROUGH
APPROACHES ON TUESDAY BRINGING CLOUDS AND A COOLING TREND.

&&

.SHORT TERM (TODAY-SAT)...MARINE LYR DEPTH RANGES FROM AROUND 1200`
ALONG THE CENTRAL COAST TO AROUND 2200` IN THE LA BASIN. HARD TO SEE
THE LOW CLOUDS NOW THOUGH WITH ALL THE HIGH CLOUDS MOVING IN AHEAD
OF THAT NEXT TROF. HIGH CLOUDS ARE PRETTY THICK AND WILL LIKELY
OBSCURE THE SUN MOST OF THE DAY AND TONIGHT. AT THIS TIME THERE IS
NO INDICATION THAT THE HIGHER CLOUDS WILL DROP ANY PRECIPITATION.
SATELLITE DERIVED RAIN RATE SHOWS NOTHING OFF OUR COAST, RADARS ARE
DRY, AND MODELS INDICATE THE MOISTURE IS ALL ABOVE 400 MB AT LEAST
FOR TODAY. THERE IS SOME LOWERING OF THE MOISTURE TONIGHT TO ABOUT
600 MB BUT THAT`S STILL WAY TOO HIGH. WILL KEEP AN EYE ON IT BUT AM
NOT EXPECTING ANY PRECIP OUT OF THIS SYSTEM EXCEPT FOR SOME POSSIBLE
DRIZZLE TONIGHT WITH A DEEPENED MARINE LYR (ASSUMING IT CAN REFORM
UNDER THE THICK HIGHER CLOUDS) AND MAYBE AN ISOLATED SHOWER OVER THE
MTNS FRI. NOT MUCH CHANGE IN TEMPS FOR COASTAL AREAS NEXT COUPLE
DAYS BUT VALLEYS AND OTHER INLAND AREAS WILL COOL ABOUT 5 DEGREES
TODAY AND ANOTHER FEW DEGREES FRIDAY.

***FROM PREVIOUS DISCUSSION***

A WEAK RIDGE MOVES IN BEHIND THE TROF FOR SATURDAY. THE HIGH CLOUDS
WILL MOVE OFF TO THE EAST BUT MOST OF THE COASTS AND VLYS WILL SEE
LOW CLOUDS IN THE MORNING...THE VLYS WILL HAVE A LITTLE LESS
COVERAGE AS THE HIGHER HGTS WILL SMOOSH THE CLOUDS SOME. THE
INTERIOR WILL WARM BUT THE COASTS AND VLYS WILL ONLY RISE SLIGHTLY
AS THE MARINE LAYER AND ONSHORE FLOW WILL PUT THE LID ON THE WARMING.

MAYBE A LITTLE WEAK SUNDOWNER SAT NIGHTS AS WELL AS SOME I-5
CORRIDOR WINDS.

.LONG TERM (SUN-WED)...
THE RIDGING PEAKS SUNDAY AND MAX TEMPS WILL PEAK. THERE WILL BE SOME
MORNING STRATUS  ACROSS THE COASTS BUT ONLY PATCHY CLOUDS FOR THE
MORNINGS. MOST AREAS WILL WARM TO ABOVE NORMAL IN THE AFTERNOON
UNDER PLENTY OF LATE APRIL SUNSHINE AND RISING HGTS.

NOT MUCH CHANGE MONDAY. THE RIDGE MOVES A LITTLE TO THE EAST AND
FLATTENS OUT SOME. THE CLOUD PATTERN WILL BE VERY SIMILAR TO SUNDAYS
AND MAX TEMPS WILL BE CLOSE AS WELL MAYBE A DEGREE COOLER.

A FAIRLY LARGE TROF WILL SWING THROUGH THE AREA TUESDAY AND EXIT
WEDNESDAY. IT LOOKS PRETTY DRY SO JUST LOOK FOR A DEEP MARINE LAYER
(MAYBE SOME DRIZZLE) AND MOSTLY CLOUDY SKIES. MAX TEMPS SHOULD DROP
PRECIPITOUSLY WITH CLOUDY SKIES AND FALLING HGTS.

A LITTLE LESS CLOUDS WEDNESDAY ALONG WITH A SLIGHT WARMING TREND AS
HGTS RISE IN THE WAKE OF THE TROF.

&&

.AVIATION...17/1740Z
MARINE LAYER TOP NEAR 022 AROUND KLAX AND 012 AROUND KSMX. A SOLID
BKN-OVC200 DECK WILL MAKE IT VERY DIFFICULT TO SEE LOWER CLOUDS
LEADING TO LOW CONFIDENCE ON SHORT-TERM TIMING. KLAX AND KSBA HAVE A
40 PERCENT CHANCE OF HAVING MVFR CIGS ALL DAY...WITH KOXR HAVING A
70 PERCENT CHANCE. KSBP KSMX SHOULD SEE SOME VFR CONDITIONS AFTER 20
OR 21Z...BUT AN EARLY RETURN IS LIKELY ESPECIALLY AT KSMX WITH A
RETURN WINDOW OF 22-02Z. EXPECTING A MUCH DEEPER MARINE LAYER
TONIGHT INTO FRIDAY WITH RETURN OF WIDESPREAD STRATUS.

KLAX...MODERATE CONFIDENCE OF MVFR CIGS AS PREVAILING CONDITION
TODAY. 2-4 HOURS OF SCT CONDITIONS IS EXPECTED...BUT 40 PERCENT
CHANCE OF CIGS ALL DAY. HIGH CLOUDS ARE BLOCKING CLEAR VIEW OF
SATELLITE SO TIMING AND UPDATES WILL HAVE LOW CONFIDENCE. SOUTHEAST
WINDS SHOULD STAY BELOW 8 KT BEFORE TURNING SOUTH TO SOUTHWEST AFTER
20Z.

KBUR...MODERATE CONFIDENCE IN MVFR CIGS OR HAZE THROUGH
19Z...IMPROVING TO VFR BY 21Z. HIGH CONFIDENCE IN MVFR CIGS
RETURNING TONIGHT...BUT TIMING CONFIDENCE IS LOWER THAN USUAL DUE TO
HIGH CLOUDS BLOCKING VIEW FROM SATELLITE.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).

&&

$$

PUBLIC...MW/RORKE
AVIATION...KITTELL

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