Wind Advisory 11, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
340 AM PST FRI FEB 8 2013

.SYNOPSIS...
A COLD UPPER LEVEL LOW WILL BRING SHOWERS AND LOW ELEVATION SNOW
SHOWERS TO THE REGION THROUGH. THERE WILL ALSO BE A SLIGHT CHANCE OF
THUNDERSTORMS...SOME WITH SMALL HAIL. IT WILL BE BREEZY TO
WINDY THROUGH TONIGHT AND IT WILL BE COLD. TRAVEL MAY BE
SIGNIFICANTLY DISRUPTED BY SNOW ACCUMULATIONS THROUGH THE MOUNTAINS.
THE UPPER LOW WILL MOVE EAST OF THE REGION SATURDAY SO IT WILL BE
DRY...BUT IT WILL REMAIN CHILLY. A SLOW WARMING TREND IT EXPECTED TO
BEGIN SUNDAY...WITH DAYTIME TEMPERATURES BACK UP TO NEAR NORMAL BY
MIDWEEK.

&&

.SHORT TERM (TODAY-SUN)...AN COLD AND ENERGETIC UPPER LOW CENTERED
NEAR SAN FRANCISCO EARLY THIS MORNING WILL DROP SOUTHEASTWARD JUST
TO THE NORTH OF THE FORECAST AREA TODAY AND TONIGHT. WHILE MOISTURE
IS LACKING WITH THIS SYSTEM...STRONG HEIGHTS FALLS HAVE HELPED TO
MAKE THE MOIST OF ANY AVAILABLE MOISTURE. SHOWER ACTIVITY
ASSOCIATED WITH THE UPPER LOW HAS PUSHED INTO THE CENTRAL COAST.
UNFORTUNATELY...THE VANDENBERG DOPPLER IS NOT FUNCTIONING AND WILL
BE DOWN THROUGH THE DURATION OF THIS STORM SYSTEM. MOIST AND
INCREASINGLY CYCLONIC FLOW HAS ALSO CAUSED SHOWER ACTIVITY TO DEVELOP
ACROSS L.A. COUNTY...WHERE THE WLY FLOW DIRECTION WAS MOST CONDUCIVE
TO PRODUCING LIFT TO WRING OUT ANY LOW LEVEL MOISTURE.

EXPECT SHOWER ACTIVITY WITH THE UPPER LOW TO OVERSPREAD THE REGION
THIS MORNING...THEN CONTINUE THROUGH THIS EVENING BEFORE ENDING FROM
NORTHWEST TO SOUTHEAST TONIGHT. WITH 500 MB TEMPS DROPPING TO
BETWEEN -30 AND -33 ACROSS THE REGION...THERE SHOULD BE ENOUGH
INSTABILITY TO WARRANT A CHANCE OF THUNDERSTORMS ACROSS THE
REGION...DESPITE THE FACT THAT SFC TEMPS WILL BE IN THE 50S AT BEST
TODAY. ANY THUNDERSTORM COULD PRODUCE SMALL HAIL. RAINFALL AMOUNTS
ARE EXPECTED TO AVERAGE ONE QUARTER TO ONE HALF INCH ACROSS SLO AND
SBA COUNTIES...AND ACROSS EASTERN SECTIONS OF L.A. COUNTY...WITH ONE
TENTH TO ONE QUARTER INCH ELSEWHERE. IN THE FOOTHILLS OF ERN L.A.
COUNTY AND ON NORTHERN SLOPES...LIQUID EQUIVALENT PRECIP TOTALS OF
ONE HALF TO ONE INCH ARE POSSIBLE...MUCH OF WHICH WILL FALL AS
SNOW.

THE MOST IMPORTANT IMPACT OF THIS STORM SYSTEM WILL BE THE LOW
ELEVATION SNOW...AND THE LIKELIHOOD OF MAJOR DISRUPTIONS IN TRAVEL
TODAY THROUGH EARLY SATURDAY...ESPECIALLY ACROSS THE GRAPEVINE.
SNOW LEVELS WILL COLLAPSE FROM 4500 FEET TO BETWEEN 2500 AND 3000
THIS MORNING ACROSS THE REGION. MAJOR ROADS THAT WILL LIKELY
BE AFFECTED BY ACCUMULATING SNOW DURING THE MORNING COMMUTE
INCLUDE INTERSTATE 5 (FROM NORTH OF CASTAIC TO THE GRAPEVINE) AND
POSSIBLY HIGHWAY 14 THROUGH SOLEDAD CANYON INTO THE ANTELOPE
VALLEY...AND HIGHWAY 138 IN THE ANTELOPE VALLEY. SNOW LEVELS WILL
CONTINUE TO FALL TODAY...AND BY EVENING WILL LIKELY BE DOWN
TO 2000 FEET...AND POSSIBLY SLIGHTLY LOWER IN HEAVIER SHOWERS OR
THUNDERSTORMS. IT APPEARS THAT SNOW ACCUMULATIONS OF 6 TO 10 INCHES
ARE LIKELY AT ELEVATIONS ABOVE 4000 FEET ACROSS THE NORTHERN
MOUNTAIN SLOPES OF L.A. AND VTU COUNTY...INCLUDING PLACES SUCH AS
LOCKWOOD VALLEY AND FRAZIER PARK...AND ACROSS THE EASTERN SAN
GABRIEL MOUNTAINS.

HAVE UPGRADED TO WINTER STORM WARNING FOR THE MTNS OF L.A. AND VTU
COUNTIES...AND CONTINUED THE WINTER WEATHER ADVISORIES FOR THE MTNS
OF SBA COUNTIES. SNOW ACCUMULATIONS OF 1 TO 4 INCHES ARE EXPECTED
BETWEEN ABOUT 3000 AND 4000 FEET. THIS WOULD LIKELY AFFECT FOOTHILL
LOCATIONS ABOVE THE ANTELOPE VALLEY AND CUYAMA VALLEY...SO HAVE
ISSUED WINTER WEATHER ADVISORIES THERE. WOULD NOT BE SURPRISED TO
SEE LOCAL TOTALS UP TO AN INCH ON THE VALLEY FLOORS OF EACH
LOCATION. EVEN HIGHER FOOTHILL COMMUNITIES OF THE LOS ANGELES AND
VENTURA COUNTY VALLEYS COULD SEE A DUSTING OF SNOW...ESPECIALLY NEAR
THE SANTA CLARITA VALLEY AND COMMUNITIES ABOVE INTERSTATE 210.

GUSTY WEST WINDS WILL AFFECT MUCH OF THE REGION...AND WILL LIKELY
REACH WIND ADVISORY LEVELS ACROSS CSTL SXNS OF L.A. AND VTU COUNTIES
THROUGH THIS EVENING. ADVISORIES MAY HAVE TO BE EXPANDED TO OTHER
COASTAL AREAS AS WELL.

ANY SHOWERS WILL END BY SAT MORNING...THEN DRY AND COOL WEATHER WILL
PREVAIL SAT THROUGH SUNDAY. IT WILL BE VERY CHILL SAT NIGHT AND SUN
NIGHT...AND FROST ADVISORIES MAY HAVE TO BE ISSUED FOR COASTAL
SECTIONS OF SLO AND SBA COUNTIES...AND THE INTERIOR VLYS OF VTU
COUNTY SUCH AS THE OJAI VALLEY.

.LONG TERM (MON-THU)...WILL BE ISSUED SHORTLY.

&&

.AVIATION...08/1200Z...LOW TO MODERATE CONFIDENCE WITH 12Z TAF OVER
THE NEXT 12 HOURS..WITH MORE CONFIDENCE AFTER 00Z SAT. MVFR CIGS
SHOULD PERSIST THROUGH MUCH THE DAY AT ALL TAF SITES...WITH A 40
PERCENT CHANCE OF IFR CONDS IN SHOWERS. HIGHER CONFIDENCE WITH VFR
CONDS THIS EVENING THROUGH SATURDAY MORNING. THERE WILL BE A SLIGHT
CHANCE OF THUNDERSTORMS TODAY WITH COLD UPPER LOW MOVING OVERHEAD. Z
LEVEL TO BE AROUND 3000 TO 4000 FT THIS MORNING THROUGH THIS
AFTERNOON.

KLAX...LOW TO MODERATE CONFIDENCE OVERALL IN THE CURRENT TAF DUE TO
UNCERTAINTIES WITH CIGS THROUGH 03Z. GOOD CONFIDENCE WITH WIND
STRENTHN AND WESTERLY DIRECTION THROUGH EARLY THIS EVENING. HIGHER
CONFIDENCE WITH VFR CONDS AS WELL.

KBUR...MODERATE CONFIDENCE OVERALL IN THE CURRENT TAF DUE TO
UNCERTAINTIES WITH THE TIMING OF IMPROVED CIGS TO VFR THIS EVENING
WHICH COULD BE OFF PLUS/MINUS AND HOUR OR TWO. 30 PERCENT CHANCE FOR
RETURN OF MVFR CIGS BY 10Z...WITH A 50 PERCENT CHANCE VFR GIGS WILL
PERSIST 10Z-17Z.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING (SEE LAXWSWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
WINTER WEATHER ADVISORY (SEE LAXWSWLOX).
GALE WARNING (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).

&&

PUBLIC...BRUNO
AVIATION...KAPLAN

WWW.WEATHER.GOV/LOSANGELES

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
305 PM PST THU FEB 7 2013

CAZ034>041-044>046-051>054-059-087-088-547-548-081400-
SAN LUIS OBISPO COUNTY CENTRAL COAST-
SANTA BARBARA COUNTY CENTRAL COAST-SANTA YNEZ VALLEY-
SAN LUIS OBISPO COUNTY INTERIOR VALLEYS-CUYAMA VALLEY-
SANTA BARBARA COUNTY SOUTH COAST-VENTURA COUNTY COAST-
LOS ANGELES COUNTY COAST INCLUDING DOWNTOWN LOS ANGELES-
VENTURA COUNTY INTERIOR VALLEYS-VENTURA COUNTY COASTAL VALLEYS-
SANTA MONICA MOUNTAINS RECREATIONAL AREA-
SAN LUIS OBISPO COUNTY MOUNTAINS-
SANTA BARBARA COUNTY MOUNTAINS-VENTURA COUNTY MOUNTAINS-
LOS ANGELES COUNTY MOUNTAINS EXCLUDING THE SANTA MONICA RANGE-
ANTELOPE VALLEY-CATALINA ISLAND-SANTA CLARITA VALLEY-
LOS ANGELES COUNTY SAN FERNANDO VALLEY-
LOS ANGELES COUNTY SAN GABRIEL VALLEY-
305 PM PST THU FEB 7 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE... TODAY AND TONIGHT

BEACHGOERS WILL FACE AN INCREASED RISK OF RIP CURRENTS TODAY AND
THIS EVENING. GUSTY WINDS WILL MAKE DRIVING DIFFICULT OVER THE
ANTELOPE VALLEY.

* WIND ADVISORY..............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

* HIGH RIP CURRENT RISK......SEE FZUS56 KLOX - SRFLOX FOR DETAILS *

* SPECIAL WEATHER STATEMENT..SEE WWUS86 KLOX - SPSLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... FRIDAY THROUGH WEDNESDAY

A COLD STORM SYSTEM WILL BRING SHOWERS...A SLIGHT CHANCE OF
THUNDERSTORMS...LOW ELEVATION SNOW...AND WINDY CONDITIONS EARLY
FRIDAY MORNING THROUGH EARLY SATURDAY MORNING. THE MOUNTAINS WILL
HAVE THE MOST HAZARDOUS WEATHER WITH NUMEROUS ROAD CLOSURES LIKELY
DUE TO ACCUMULATING SNOW AND ICY CONDITIONS. MARINERS WILL FACE THE
POSSIBILITY OF GALE FORCE WINDS ACROSS THE OUTER WATERS ON FRIDAY AS
WELL. A BUILDING SWELL AND HIGH TIDES WILL BRING THE POSSIBILITY OF
MINOR COASTAL FLOODING FOR LOW-LYING AREAS...AS WELL AS AN INCREASED
RISK FOR DANGEROUS RIP CURRENTS.

COLD AND SUB-FREEZING MORNING TEMPERATURES ARE EXPECTED SATURDAY
THROUGH MONDAY...WHICH COULD DAMAGE PLANTS.

* COASTAL FLOOD ADVISORY.....SEE WGUS46 KLOX - CFWLOX FOR DETAILS *

* WIND ADVISORY..............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

* GALE WARNING...............SEE WHUS76 KLOX - MWWLOX FOR DETAILS *

* MARINE WEATHER STATEMENT...SEE FZUS76 KLOX - MWSLOX FOR DETAILS *

* HIGH RIP CURRENT RISK......SEE FZUS56 KLOX - SRFLOX FOR DETAILS *

* SPECIAL WEATHER STATEMENT..SEE WWUS86 KLOX - SPSLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.