514 
FXUS66 KLOX 131800
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1040 AM PST THU NOV 13 2014

...AVIATION DISCUSSION UPDATED...

.SYNOPSIS...

A WEAK FRONT WILL BRING SCATTERED TO ISOLATED SHOWERS TO NORTHERN 
AREAS TODAY. COOL WEATHER WILL CONTINUE THROUGH SATURDAY...THEN 
UPPER LEVEL RIDGING AND OFFSHORE FLOW WILL BRING DRIER AND WARMER 
WEATHER SUNDAY THROUGH MONDAY WITH LOCALLY GUSTY WINDS. TEMPERATURES 
WILL LIKELY REMAIN ABOVE NORMAL THROUGH TUESDAY. AN UPPER TROUGH 
COULD BRING LIGHT RAIN TO FAR NORTHERN AREAS BY MID WEEK.

&&

.SHORT TERM (TODAY-SAT)...

SATELLITE AND RADAR IMAGERY THIS MORNING SHOWS A WEAK COLD FRONT 
APPROACHING THE CENTRAL COAST...WITH SCATTERED SHOWERS MOVING 
ONSHORE. FORECAST OF SCATTERED TO ISOLATED SHOWERS FOR TODAY FOR 
AREAS N OF PT CONCEPTION LOOKS GOOD. PRECIP AMOUNTS WILL BE LIGHT 
WHERE IT DOES RAIN...ON THE ORDER OF A FEW HUNDREDTHS OF AN INCH. 
ALSO ADDED SOME ISOLATED SHOWERS TO THE MOUNTAINS IN NORTHERN 
VENTURA COUNTY. RADAR SHOWS SOME WEAK SHOWER ACTIVITY IN THAT AREA 
AND WEB CAMS SHOWED SOME WET/DAMP ROADS. ALSO REDUCED THE CLOUD 
COVER TO PARTLY CLOUDY FOR MUCH OF THE VENTURA AND LOS ANGELES 
COUNTY COASTAL AND VALLEY AREAS THIS MORNING...EXCEPT FOR SOME AREAS 
ALONG THE IMMEDIATE COAST. THERE SHOULD BE AN INCREASE CLOUDS THIS 
AFTERNOON AS THE WEAKENING FRONT PUSHES THROUGH THE REGION BY THIS 
EVENING.

A WEAK UPPER-LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA LATE 
TONIGHT INTO FRIDAY MORNING. CURRENT FORECAST CALLS FOR A SLIGHT 
CHANCE OF RAIN FOR THE LA AND VENTURA COUNTY COASTAL AREAS WITH 
THAT. HOWEVER...WILL LIKELY BE REMOVING IT FROM THE FORECAST WITH 
THE AFTERNOON UPDATE...AS MOST RECENT MODEL RUNS INDICATE THE LOWER 
LEVELS WILL DRY OUT WITH NW FLOW SETTING UP BEHIND THE PASSAGE OF 
THE COLD FRONT THIS EVENING. IN FACT...THERE MAY NOT BE MUCH CLOUDS 
AT ALL TOMORROW MORNING FOR THE LA AND VENTURA COUNTY COASTAL AND 
VALLEY AREAS. LOOKS MORE LIKE A SLIGHT CHANCE OF SOME NORTH SLOPE 
SHOWERS IN NORTHERN VENTURA COUNTY AND NEAR THE GRAPEVINE LATE 
TONIGHT AND FRIDAY MORNING. 

***FROM PREVIOUS DISCUSSION***

GUSTY WEST WINDS WILL DEVELOP IN THE ANTELOPE VALLEY TODAY. 
WINDS WILL LIKELY GET CLOSE TO ADVISORY LEVELS...BUT AT THIS 
TIME...EXPECT 45 MPH WIND GUSTS TO REMAIN CONFINED TO THE WINDIER 
AREAS IN THE FOOTHILLS NEAR LAKE PALMDALE AND POPPY PARK. MAX TEMPS 
SHOULD BE DOWN A TAD TODAY...REMAINING SLIGHTLY BELOW NORMAL IN MOST 
AREAS.

A BROAD WEST NORTHWEST FLOW PATTERN WILL SET UP ACROSS THE REGION 
FRI NIGHT AND SAT...AND HEIGHTS WILL RISE A BIT. OFFSHORE N-S 
GRADIENTS WILL DEVELOP ACROSS SLO AND SBA COUNTIES. THIS SHOULD 
ALLOW FOR SOME REDUCTION IN LOW CLOUDINESS THERE...ESPECIALLY IN 
COASTAL SECTIONS OF SLO COUNTY AND ON THE SBA COUNTY S COAST. THERE 
COULD EVEN BE SOME LOCALLY GUSTY WINDS THROUGH AND BELOW PASSES AND 
CANYONS OF THE SANTA YNEZ RANGE. ELSEWHERE...THERE WILL STILL BE 
ABUNDANT LOW LEVEL MOISTURE...ESPECIALLY ACROSS L.A. AND VTU 
COUNTIES. THE WRF SHOWS A DECENT EDDY CRCLN DEVELOPING ACROSS 
THE INNER WATERS. EXPECT WIDESPREAD LOW CLOUDS IN COASTAL AND VALLEY 
AREA OF L.A. AND VTU COUNTIES FRI NIGHT/SAT MORNING. SKIES SHOULD 
BECOME MOSTLY SUNNY IN ALL AREAS SAT AFTERNOON...ALTHOUGH THE LATEST
RUN OF THE WRF SUGGESTS SOME MOISTURE MAY LINGER ACROSS L.A. COUNTY. 
THERE SHOULD BE A BIT OF WARMING ON SAT...ESPECIALLY ACROSS SLO AND 
SBA COUNTIES.    

.LONG TERM (SUN-WED)...A SHARP TROUGH WILL DIG SOUTH SOUTHWESTWARD 
INTO THE GREAT BASIN SAT NIGHT AND SUN. THIS SHOULD BRING SOME 
COOLING TO THE MTNS AND DESERTS AS HEIGHTS AND THICKNESSES FALL. LOW 
LEVEL FLOW ON THE LATEST MODEL RUNS DEFINITELY LOOKS MORE NLY RATHER 
THAN NELY...SO GUSTY WINDS SHOULD BE FOCUSED THROUGH AND BELOW 
PASSES AND CANYONS OF THE SANTA YNEZ RANGE AND THROUGH THE I-5 
CORRIDOR. GUSTY WINDS COULD SPREAD INTO THE L.A. COUNTY VLYS SUNDAY. 
SKIES SHOULD BE MOSTLY CLEAR. MAX TEMPS SHOULD BE UP A FEW DEGREES 
IN COASTAL AND VALLEY AREAS ON SUNDAY. AN AMPLIFYING UPPER RIDGE 
WILL BUILD INTO THE REGION ON MONDAY...AND LOW LEVEL FLOW WILL TURN 
A BIT MORE NELY. THIS COULD BRING SOME LOCALLY GUSTY WINDS TO 
PORTIONS OF L.A. AND VTU COUNTIES...BUT WINDS DO NOT LOOK TOO 
SIGNIFICANT. THERE WILL BE SOME ADDITIONAL WARMING...AND IT WILL 
BECOME VERY DRY IN THE MTNS AND FOOTHILLS. AN UPPER LOW WILL 
APPROACH THE WEST COAST ON TUE. HIGH CLOUDS SHOULD INCREASE ACROSS 
THE REGION...AND THERE SHOULD BE SOME COOLING...ESPECIALLY WEST OF 
THE MTNS AS FLOW TURNS ONSHORE. THERE IS A SLIGHT CHANCE OF SOME 
RAIN TUE NIGHT...MAINLY N OF PT CONCEPTION...BUT IT APPEARS THAT THE 
UPPER LOW WILL WEAKEN AND REMAIN TO THE SOUTHWEST OF THE REGION. 
EXPECT PARTLY CLOUDY AND COOLER WEATHER FOR WED.

&&

.AVIATION...13/1230Z...

AT 1730Z AT LAX... THERE WAS NO INVERSION.

OVERALL...LOW TO MODERATE CONFIDENCE IN THE 18Z TAFS.  A WEAK COLD 
FRONT WILL MOVE THROUGH THE REGION TODAY BRINGING VARYING CIG 
HEIGHTS TO COASTAL AND ADJACENT VALLEY SITES.  SOME CLEARING 
EXPECTED TONIGHT WHICH WILL BRING THE ADDITIONAL POSSIBILITY OF 
VARYING VSBYS TO THE SAME LOCATIONS.  OTHERWISE AND ELSEWHERE VFR 
CONDITIONS WILL PREVAIL.  GUSTY WINDS ARE EXPECTED IN THE 
ANTELOPE VALLEY TODAY.  

KLAX...LOW TO MODERATE CONFIDENCE IN THE 18Z TAF.  LOW CLOUDS WILL 
BUILD IN TODAY AHEAD OF THE COLD FRONT BUT THESE SHOULD ELEVATE BY 
MIDDAY AS HIGHER CLOUDS MOVE OVER THE REGION.  A TEN PERCENT CHANCE 
OF DRIZZLE FRIDAY MORNING AS MVFR VSBYS DEVELOP.

KBUR...MODERATE CONFIDENCE IN THE 18Z TAF.  LOW CLOUDS WILL BUILD IN 
TODAY AHEAD OF THE COLD FRONT BUT THESE SHOULD ELEVATE BY MIDDAY AS 
HIGHER CLOUDS MOVE OVER THE REGION.  A TEN PERCENT CHANCE OF DRIZZLE 
FRIDAY MORNING AS MVFR VSBYS DEVELOP.

&&

.MARINE...13/900 AM PST...

OUTER WATERS...SMALL CRAFT ADVISORY LEVEL NORTHWEST WINDS BEGIN 
FRIDAY MORNING FROM POINT SAL TO THE CHANNEL ISLANDS AND SOUTH TO 
SAN NICOLAS ISLAND... AND BEGIN FRIDAY AFTERNOON NORTH OF POINT SAL 
TO OFF THE COAST OF POINT PIEDRAS BLANCAS.  HAZARDOUS SEAS WITH 
SWELL HEIGHTS AT OR GREATER THAN 10 FEET WILL BEGIN FRIDAY MORNING.

INNER WATERS...WEST TO NORTHWEST LOCAL GUSTS TO 25 KNOTS IN THE 
WESTERN PORTION OF THE INNER SANTA BARBARA CHANNEL BOTH FRIDAY AND 
SATURDAY AFTERNOON AND EVENINGS. A FIFTY PERCENT CHANCE OF SWELLS OF 
4 TO 5 FEET AT 13 TO 14 SECOND PERIODS IN AND AROUND VENTURA HARBOR 
BY LATE FRIDAY. 

&&


.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

$$

PUBLIC...SS/DB
AVIATION...KJ
MARINE...KJ
SYNOPSIS...SS/DB

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