Winter Storm Warning 12, NWS San Diego, CA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
900 PM PST TUE DEC 28 2010

.SYNOPSIS...A STRONG COLD FRONT WAS MOVING RAPIDLY DOWN THE STATE
EARLY TONIGHT. RAIN WILL BEGIN LATE TONIGHT AND SPREAD SOUTHEAST
WEDNESDAY WITH HEAVY RAIN AT TIMES AND STRONG GUSTY WINDS MAINLY IN
THE MOUNTAINS AND UPPER DESERTS. STRONG GUSTY WINDS WILL CONTINUE
INTO EARLY THURSDAY IN THE MOUNTAINS AND UPPER DESERTS. SHOWERS ARE
EXPECTED TO CONTINUE THROUGH EARLY THURSDAY MORNING. A COLD TROUGH
WILL BE OVER THE AREA THURSDAY THROUGH FRIDAY WITH COLD
TEMPERATURES. A WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER SATURDAY.
A WEAK SYSTEM MAY MOVE OVER SUNDAY WITH SOME RAIN. A TROUGH IS
FORECAST TO REMAIN OVER THE AREA MONDAY THROUGH TUESDAY.

&&

.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.

A FAST COLD FRONT WAS HURLING TOWARD SOCAL EARLY TONIGHT. IT WAS
CLOSING IN ON POINT CONCEPTION AT 9 PM. RAIN MAY BEGIN IN ORANGE
COUNTY AND TO THE EAST BY AROUND 2 AM. HEAVY RAIN IS EXPECTED IN
THAT AREA AROUND 6 AM TO 9 AM AND IN SAN DIEGO COUNTY AROUND 8 AM TO
11 AM. STRONG GUSTY SOUTHWEST WINDS WILL MOVE IN WITH THE FRONT
WEDNESDAY MORNING WITH VERY STRONG WINDS IN THE MOUNTAINS AND UPPER
DESERTS AND AT LEAST BREEZY ELSEWHERE. SNOW LEVEL WILL BE AROUND 6K
FT LATE TONIGHT THEN DROP TO AROUND 5K FT WEDNESDAY AND DOWN TO 4K
FT AND LOCALLY LOWER TO AROUND 3K FT WEDNESDAY NIGHT. RAIN EXPECTED
TO BE AROUND ONE HALF INCH TO THREE QUARTERS OF AN INCH IN THE
COASTAL BASIN TO ONE INCH PLUS IN THE MOUNTAINS WITH A HALF INCH IN
THE UPPER DESERTS TO ONE QUARTER INCH IN THE LOWER DESERTS. ABOUT
HALF A FOOT OF SNOW IS EXPECTED IN THE MOUNTAINS WITH ONE FOOT PLUS
POSSIBLE IN THE HIGHER ELEVATIONS. LIGHT SNOW SHOWERS ARE POSSIBLE
IN THE UPPER DESERTS WEDNESDAY LATE AFTERNOON THROUGH THE NIGHT. THE
FRONT WILL MOVE OUT BY LATE WEDNESDAY AFTERNOON WITH STRONG GUSTY
WINDS TURNING TO THE WEST. SHOWERS ARE EXPECTED AFTER THE FRONT
THROUGH WEDNESDAY NIGHT AND INTO EARLY THURSDAY MORNING ALONG WITH
STRONG GUSTY NORTHWEST WINDS IN THE UPPER DESERTS AND MOUNTAINS. A
COLD TROUGH WILL BE OVER SOCAL THURSDAY THROUGH FRIDAY WITH
COOL/COLD HIGH TEMPERATURES AND QUITE COLD MORNING LOW TEMPERATURES.
A WEAK RIDGE OF HIGH PRESSURE IS EXPECTED SATURDAY. A WEAK TROUGH
AND FRONT IS FORECAST FOR SUNDAY WITH RAIN POSSIBLE. A WEAK TROUGH
IS EXPECTED TO REMAIN OVER SOCAL MONDAY THROUGH TUESDAY. THE MODELS
CONTINUE TO DIFFER ON THE WEEKEND INTO NEXT WEEK. THE ECMWF MODEL IS
WHAT THE FORECAST IS BASED ON. MUCH COOLER WEDNESDAY...MUCH COLDER
THURSDAY WITH LITTLE CHANGE FRIDAY...WARMER SATURDAY...COOLER
SUNDAY...LITTLE CHANGE MONDAY AND TUESDAY.

&&

.AVIATION...
290500Z...AREAS OF VIS 3SM IN FOG AND RAIN...LOCALLY BLO 1SM WILL
ALSO OCCUR...MAINLY AFTER 09Z. CONDITIONS WILL IMPROVE TO MVFR AFTER
20Z WED BUT LINGERING SHOWERS COULD BRING LOCALLY IFR/LIFR
CONDITIONS AT TIMES THROUGH 04Z THU. GUSTY SW WINDS TO 30 KTS WILL
DEVELOP OVER THE MOUNTAINS AND DESERT FOOTHILLS WED MORNING...
INCREASING TO LOCAL 50 KT GUSTS WEDNESDAY AFTERNOON.

&&

.MARINE...
AN APPROACHING WINTER STORM WILL BRING STRONG WINDS...LARGE SWELLS
AND ROUGH SEAS TO THE COASTAL WATERS ON WED...CONTINUING INTO THU.
THE WINDS AND SWELL WILL PEAK LATE WED NIGHT/EARLY THU MORNING WITH
SUSTAINED WINDS IN EXCESS OF 20 KTS AND GUSTS OVER 30 KTS. THIS WILL
LIKELY RESULT IN COMBINED SEAS OF 10 FT OR MORE. THE INCREASING
SWELLS WILL ALSO BRING THE CHANCE FOR HIGH SURF ON THU ALONG WITH
POSSIBLE COASTAL FLOODING DURING THE MORNING HIGH TIDE.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...

SPECIAL WEATHER STATEMENT. SEE LAXSPSSGX.

WINTER STORM WARNING FROM 2 AM WEDNESDAY THROUGH 8 PM WEDNESDAY FOR
THE SAN BERNARDINO AND RIVERSIDE COUNTY MOUNTAINS. SEE LAXWSWSGX.

HIGH WIND WATCH WEDNESDAY EVENING THROUGH LATE WEDNESDAY NIGHT
FOR THE SAN BERNARDINO AND RIVERSIDE COUNTY MOUNTAINS. SEE LAXNPWSGX.

HIGH WIND WARNING LATE TONIGHT THROUGH LATE WEDNESDAY NIGHT FOR THE
MOUNTAINS AND UPPER DESERTS. SEE LAXNPWSGX.

SMALL CRAFT ADVISORY FOR COASTAL WATERS OFF SAN DIEGO COUNTY. SEE
LAXMWWSGX.

&&

PUBLIC...WHITLOW
AVIATION...MACKECHNIE

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN DIEGO CA
400 PM PST TUE DEC 28 2010

CAZ042-043-048-050-055>058-060>062-291200-
ORANGE COUNTY COASTAL AREAS-
SAN DIEGO COUNTY COASTAL AREAS-
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN DIEGO COUNTY VALLEYS-
SAN BERNARDINO COUNTY MOUNTAINS-
RIVERSIDE COUNTY MOUNTAINS-
SANTA ANA MOUNTAINS AND FOOTHILLS-
SAN DIEGO COUNTY MOUNTAINS-
APPLE AND LUCERNE VALLEYS-
COACHELLA VALLEY-
SAN DIEGO COUNTY DESERTS-
400 PM PST TUE DEC 28 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR ALL OF EXTREME SOUTHWESTERN
CALIFORNIA.

.DAY ONE...THROUGH TONIGHT

A COLD FRONT WILL BRING RAIN...SNOW IN THE MOUNTAINS AND LOCAL
STRONG GUSTY SOUTHWEST WINDS BEGINNING LATE TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A STRONG WINTER STORM WILL BRING RAIN...SNOW IN THE MOUNTAINS AND
LOCAL STRONG GUSTY SOUTHWEST WINDS WEDNESDAY. STRONG GUSTY WINDS
WILL TURN TO THE WEST TO NORTHWEST WEDNESDAY NIGHT THROUGH
THURSDAY.

IT WILL BE COLD WITH WIDESPREAD FROST IN THE INLAND VALLEYS AND
LOWER DESERTS THURSDAY NIGHT AND FRIDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...SKYWARN SPOTTER ACTIVATION MAY BE
NEEDED LATE TONIGHT AND WEDNESDAY.

SGX