Wind Advisory 164, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
ISSUED BY NATIONAL WEATHER SERVICE SAN DEIGO CA
900 AM PST WED FEB 13 2008

.SHORT TERM...SHALLOW MARINE LAYER ACROSS SRN CA THIS MORNING. PRES
GRADS HAVE TURNED FROM WEAKLY OFFSHORE TO NEUTRAL OR EVEN WEAKLY
ONSHORE. THESE ARE PERFECT CONDITIONS FOR DENSE FOG...AND INDEED
DENSE FOG PUSHED INTO SOME COASTAL AREAS BUT HAD BECOME PATCHY BY
MID MORNING. THE DENSE FOG SHOULD BURN OFF BY LATE MORNING...BUT
THERE SHOULD BE ENOUGH HIGH CLOUDINESS AROUND TO KEEP PARTLY CLOUDY
WORDING FOR THE DAY. IN ADDITION...THE WRF SHOWS LOW LVL MOISTURE
INCREASING ACROSS THE AREA THIS AFTERNOON AS ONSHORE GRADS REALLY
INCREASE...SO IT COULD BE ONE OF THOSE DAYS WHERE LOW CLOUDS BEGIN
TO SPREAD INTO THE AREA BY LATE AFTERNOON. WINDS WILL LIKELY APCH
ADVISORY LEVELS IN THE ANTELOPE VALLEY THIS AFTERNOON. THERE WILL BE
SIGNIFICANT COOLING ACROSS THE AREA TODAY...WITH TEMPS DOWN AS MUCH
AS 15 TO 20 DEGREES IN SOME COASTAL AND VALLEY AREAS.

A STRONG UPPER LOW WILL DIG THROUGH THE GREAT BASIN LATER TODAY AND
TONIGHT. THIS WILL CAUSE RAPID DEEPENING OF THE MARINE LAYER...WITH
WDSPRD CLOUDS ACROSS ALL CSTL AND VLY AREAS...PROBABLY REACHING THE
CSTL SLOPES. DUE TO THE RAPID AND SIGNIFICANT DEEPENING OF THE
MARINE LATER...SOME DRIZZLE WILL PROBABLY FORM ACROSS THE AREA
TONIGHT.

AS THE UPPER LOW DROPS THRU NEVADA AND INTO NWRN ARIZONA LATE
TONIGHT AND THU...WINDS ALOFT WILL INCREASE DRAMATICALLY ACROSS THE
FCST AREA. STRONG SUBSIDENCE AIDED BY GOOD COLD AIR ADVECTION WITH
THE RIGHT FRONT QUADRANT OF A POWERFUL NLY JET MOVING OVER THE AREA
SHOULD CAUSE VERY STRONG WINDS TO DEVELOP IN THE MTNS EITHER LATE
TONIGHT OR VERY EARLY THU MORNING. LOW LVL GRADS WILL RAPIDLY TURN
OFFSHORE AND INCREASE LATE TONIGHT AND THU MORNING. THE PRESENCE OF
A DEEP MARINE LAYER IN PLACE ACROSS THE AREA TONIGHT MAKES THIS
FORECAST TRICKY...BECAUSE IT OFTEN PREVENTS WINDS FROM SPREADING
INTO THE VLYS AND COASTAL AREAS. HOWEVER...WITH SO MUCH COLD AIR
ADVECTION...BELIEVE THE WRF HAS THE RIGHT IDEA IN SHOWING AN
ERADICATION OF THE MARINE INVERSION EARLY THU MORNING...WITH A RAPID
BREAKUP OF THE CLOUD FIELD W OF THE MTNS BY MID MORNING. AT THE SAME
TIME...EXPECT STRONG AND GUSTY N TO NE WINDS TO SPREAD INTO THE VLYS
AND EVENTUALLY COASTAL SECTIONS OF L.A. AND VTU COUNTIES DURING THU
MORNING.

HAVE ISSUED HIGH WIND WATCHES FOR THE MTNS AND VLY OF L.A. AND VTU
COUNTIES...SINCE WIND GUSTS COULD EXCEED 60 MPH IN THE VLYS AND 70
MPH IN THE MTNS. THE EXACT TIMING OF THE ONSET OF THE STRONG WINDS
IS A BIT PROBLEMATIC...BUT HAVE ERRED ON THE SIDE OF CAUTION BY
STARTING THE WATCH IN THE MTNS (EXCLUDING THE SANTA MONICAS) LATE
TONIGHT...AND IN THE VLYS AND SANTA MONICA MTNS JUST AFTER DAYBREAK.
IN REALITY THE STRONGEST WINDS WILL PROBABLY NOT OCCUR UNTIL LATE
MORNING OR AFTERNOON IN THE VLYS. DID NOT INCLUDE CSTL SXNS IN THE
WATCH AT THIS TIME...THINKING THAT ADVISORY LVL WINDS ARE MORE
LIKELY THERE...MAINLY FROM MALIBU TO HOLLYWOOD...AND ACROSS THE VTU
COUNTY CSTL PLAIN. ADDITIONAL COOLING IS EXPECTED THU...ESPECIALLY
IN THE MTNS AND DSRTS.

THE UPPER LOW WILL MOVE SLOWLY EWD THU NIGHT AND FRI. WHILE UPPER
SUPPORT FOR WINDS WILL GRADUALLY WEAKEN...GRADS WILL REMAIN STRONGLY
OFFSHORE...AND ADVISORY LVL WINDS WILL LIKELY CONT IN THE MTNS AND
VLYS OF L.A. AND VTU COUNTIES THU NIGHT/FRI MORNING. EXPECT WARMING
TO BEGIN ON FRI...WITH TEMPS NEAR NORMAL W OF THE MTNS.

.LONG TERM...STRONG RIDGING WILL BUILD INTO THE AREA OVER THE
WEEKEND....WITH CLEAR SKIES AND TEMPS SEVERAL DEGREES ABOVE NORMAL
ACROSS THE REGION. THERE COULD STILL BE SOME LOCALLY GUSTY WINDS SAT
MORNING...BUT NOTHING TOO SIGNIFICANT EXPECTED. AN UPPER LOW MOVING
NEWD ACROSS THE PAC WILL MOVE INTO NRN CA MONDAY. IT WILL FORCE THE
RIDGE EWD...CAUSING SOME COOLING ACROSS THE AREA MONDAY...WITH
LITTLE CHANGE ON TUE.

&&

.AVIATION...13/1700Z
A SHALLOW MARINE LAYER WITH CLOUD TOPS AROUND 700-1200 FEET MSL WILL
PERSIST THROUGH THE MORNING...DEEPEN SOME DURING THE DAY...THEN
DEEPEN RAPIDLY TO OVER 3000 FEET MSL TONIGHT. INCREASING ONSHORE
FLOW SHOULD MAKE THE DENSE FOG MORE PERSISTENT THAN IT IS DURING
MOST DENSE FOG EPISODES AT THE COASTAL AIRPORTS. LOCAL LIFR MANY
COASTAL SITES IMPROVING TO IFR TO MVFR AROUND 18Z-19Z MOST
AREAS. AFTER BURNING BACK TO THE COASTAL AIRPORTS...EXPECT MVFR TO
IFR TO PUSH INLAND AFTER 03Z. AS THE MARINE LAYER DEEPENS BASES
SHOULD LIFT TO MAINLY 1500-2000 FEET MSL AS IT MOVES INLAND THIS
AFTERNOON AND EVENING.

KLAX...MVFR CONDITIONS WILL PREVAIL...AFTER PATCHES OF LIFR FOG
LIFTS. PARTIAL CLEARING THROUGH THE AFTERNOON WITH A SEABREEZE TO 10
KTS. CLOUD BASES ARE EXPECTED TO LIFT THROUGH THE NIGHT BUT SHOULD
REMAIN MVFR. LIGHT DRIZZLE IS POSSIBLE AFTER 10Z.

KBUR...VFR THROUGH THE DAY...BUT MARINE LAYER DEEPENING SHOULD BRING
LOW CLOUDS IN AFTER 08Z. SHOULD STAY IFR/MVFR...BUT UNCERTAIN THERE.
AS NE WINDS INCREASE OVER THE MOUNTAINS TONIGHT...LLWS MAY BECOME A
CONCERN AFTER ABOUT 10Z.

.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXCWFLOX).

&&

PUBLIC...BRUNO/SGX
AVIATION...MEIER/SGX

WWW.WEATHER.GOV/LOSANGELES

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
ISSUED BY NATIOAL WEATHER SERVICE SAN DIEGO CA
957 AM PST WED FEB 13 2008

CAZ034>041-044>047-051>054-059-087-088-141400-
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-
LOS ANGELES COUNTY VALLEYS-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-
900 AM PST WED FEB 13 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE... TODAY AND TONIGHT

STRONG NORTH TO NORTHEAST WINDS ARE EXPECTED TO DEVELOP IN THE
MOUNTAINS OF LOS ANGELES AND VENTURA COUNTIES VERY LATE
TONIGHT...WITH DAMAGING WIND GUSTS POSSIBLE.

* HIGH WIND WATCH............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... THURSDAY THROUGH TUESDAY

STRONG NORTH TO NORTHEAST WINDS WILL AFFECT MUCH OF LOS ANGELES AND
VENTURA COUNTIES THURSDAY. DAMAGING WINDS ARE POSSIBLE IN THE
MOUNTAINS AND VALLEYS.

GUSTY NORTHEAST WINDS WILL CONTINUE TO AFFECT MUCH OF LOS ANGELES
AND VENTURA COUNTIES THURSDAY NIGHT AND FRIDAY...BUT THE WINDS
ARE NOT EXPECTED TO BE QUITE AS STRONG AS ON THURSDAY.

* HIGH WIND WATCH............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

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

BRUNO/SGX