River Flood Warning 6, NWS San Diego, CA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 AM PST TUE DEC 21 2010

.SYNOPSIS...MOIST SOUTHWEST FLOW WILL CONTINUE PERIODS OF RAIN AND
HIGHER ELEVATION SNOW TODAY. A STRONG...COLDER TROUGH OF LOW
PRESSURE FROM THE NORTHWEST WILL BRING NUMEROUS SHOWERS...SCATTERED
THUNDERSTORMS...AND STRONG GUSTY WINDS TONIGHT AND WEDNESDAY. FAIR
AND WARMER FOR THURSDAY AND FRIDAY. WEAK UPPER TROUGHS WILL CAUSE
SMALL CHANCES OF MAINLY LIGHT PRECIPITATION AT TIMES SATURDAY NIGHT
THROUGH EARLY NEXT WEEK.

&&

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

.SHORT TERM (REMAINDER OF TODAY-FRIDAY)...WIDESPREAD RAIN TODAY WITH
SNOW ABOVE 6000 FEET. THE 12Z NKX SOUNDING SHOWED A DEEP MOIST LAYER
WITH STRONG SW WINDS ALOFT. ONSHORE GRADIENTS WITH ABOUT 3 MB
SAN-IPL.

THE PLUME OF SUBTROPICAL MOISTURE FLOWING OUT OF THE SW WILL
CONTINUE TO BRING MAINLY LIGHT TO MODERATE PRECIP TODAY. THIS PLUME
WILL SLOWLY SHIFT SE THROUGH THIS EVENING. SNOW LEVEL NEAR 6000 FT
TODAY.

A COLD UPPER TROUGH WITH AN ASSOCIATED COLD FRONT WILL MOVE THROUGH
LATE TONIGHT AND EARLY WEDNESDAY. THIS WILL BRING NUMEROUS SHOWERS
AND SCATTERED THUNDERSTORMS. THE SHOWERS WILL TAPER OFF BY WEDNESDAY
NIGHT. THIS WILL CAUSE PERIODS OF HEAVY SHOWERS WITH ISOLATED
RAINFALL RATES IN THE ONE TO TWO INCH PER HOUR RANGE.

PREFRONTAL WINDS COULD BE NEAR ADVISORY STRENGTH FOR LATE TONIGHT
THROUGH WEDNESDAY MORNING. SNOW LEVELS MAY RISE SLIGHTLY EARLY THIS
EVENING...BEFORE LOWERING TO 5000 TO 5500 FEET WEDNESDAY. ADVISORY
SNOWFALL AMOUNTS ARE POSSIBLE ABOVE 7000 FEET THROUGH THIS
AFTERNOON. HEAVY SNOWFALL IS POSSIBLE ABOVE 6500 FEET FOR LATE
TONIGHT AND WEDNESDAY.

FAIR AND WARMER FOR THURSDAY AND FRIDAY AS HIGH PRESSURE BEGINS TO
BUILD OVER SOUTHERN CALIFORNIA.

&&

.LONG TERM (SATURDAY-TUESDAY)...CONTINUED DRY INTO SATURDAY. FOR
SATURDAY NIGHT INTO NEXT WEEK...ONSHORE FLOW WILL RETURN WITH MINOR
COOLING. LITTLE MODEL AGREEMENT ON SHORTWAVE DETAILS FOR THE WEEKEND
INTO NEXT WEEK...BUT SHORTWAVES MOSTLY PASSING BY TO THE NORTH COULD
BRING SOME MAINLY LIGHT PRECIPITATION AT TIMES.

&&

.AVIATION...
211630Z...WIDESPREAD IFR/LIFR CONDITIONS IN RAIN AND FOG WILL
CONTINUE THROUGH WEDNESDAY MORNING. HIGHER TERRAIN OBSCURED.

.MARINE...
WEST NORTHWEST SWELL WILL CONTINUE TODAY...THEN DECREASE ON
WEDNESDAY. A SOUTHWEST WIND SWELL IS EXPECTED TODAY THROUGH
WEDNESDAY. WINDS WILL CONTINUE TO BE GUSTY AT TIMES...THEN BECOMING
QUITE STRONG TONIGHT INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH
THE COASTAL WATERS WITH WINDS APPROACHING SMALL CRAFT ADVISORY
CRITERIA.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...

CA...FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR THE APPLE AND
     LUCERNE VALLEYS...COACHELLA VALLEY...ORANGE COUNTY COASTAL
     AREAS...RIVERSIDE COUNTY MOUNTAINS...SAN BERNARDINO COUNTY
     MOUNTAINS...SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE
     INLAND EMPIRE...SAN DIEGO COUNTY COASTAL AREAS...SAN DIEGO
     COUNTY DESERTS...SAN DIEGO COUNTY MOUNTAINS...SAN DIEGO
     COUNTY VALLEYS...SANTA ANA MOUNTAINS AND FOOTHILLS. SEE
     LAXFFASGX.

     WINTER WEATHER ADVISORY UNTIL 6 PM PST WEDNESDAY ABOVE 6500
     FEET FOR THE RIVERSIDE COUNTY MOUNTAINS...SAN BERNARDINO
     COUNTY MOUNTAINS. SEE LAXWSWSGX.

     WINTER STORM WARNING FROM 6 PM WEDNESDAY TO 6 PM PST THURSDAY
     ABOVE 6500 FEET FOR THE RIVERSIDE COUNTY MOUNTAINS...SAN
     BERNARDINO COUNTY MOUNTAINS. SEE LAXWSWSGX.

     FLOOD WARNING FOR THE SANTA MARGARITA AND MOJAVE RIVERS. SEE
     LAXFLWSGX.

&&

PUBLIC...ATKIN
AVIATION/MARINE...MM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN DIEGO CA
550 AM PST TUE DEC 21 2010

CAZ042-043-048-050-055>058-060>062-221400-
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-
550 AM PST TUE DEC 21 2010

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

.DAY ONE...TODAY AND TONIGHT

FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON. SEE LAXFFASGX.
WINTER WEATHER ADVISORY AND WINTER STORM WARNING FOR THE MOUNTAINS.
SEE LAXWSWSGX.

SCATTERED THUNDERSTORMS WITH SMALL HAIL...WATERSPOUTS...AND ISOLATED
TORNADOES ARE POSSIBLE LATE TONIGHT.

STRONG GUSTY WINDS TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON. SEE LAXFFASGX. WINTER
STORM WARNING FOR THE MOUNTAINS THROUGH WEDNESDAY AFTERNOON. SEE
LAXWSWSGX.

SCATTERED THUNDERSTORMS WITH SMALL HAIL...WATERSPOUTS...AND ISOLATED
TORNADOES ARE POSSIBLE WEDNESDAY.

STRONG GUSTY WINDS WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SKYWARN HAS BEEN ACTIVATED IN ORANGE AND SAN BERNARDINO COUNTIES.
ACTIVATION WILL ALSO BE NEEDED IN SAN DIEGO AND RIVERSIDE COUNTIES
TUESDAY AND WEDNESDAY.

MARTIN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN DIEGO CA
933 AM PST TUE DEC 21 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0530 AM     FLASH FLOOD      APPLE VALLEY            34.53N 117.21W
12/21/2010                   SAN BERNARDINO     CA   TRAINED SPOTTER

            WIDESPREAD URBAN FLOODING/PONDING. MISC STALLED
            VEHICALES. NAVAJO ROAD CLOSED AT OTTAWA DUE TO FLOODING.

0530 AM     FLASH FLOOD      CORONADO                32.69N 117.18W
12/21/2010                   SAN DIEGO          CA   TRAINED SPOTTER

            STREET FLOODING IN CORONADO. BOTH NORTHBOUND LANES ON
            ORANGE AVE BLVD.WITH 3 TO 4 INCHES OF WATER. 6 TO 7
            INCHES OF WATER ON 1ST STREET NEAR FERRY LANDING

0850 AM     FLASH FLOOD      2 NE RANCHO SANTA MARGA 33.66N 117.58W
12/21/2010                   ORANGE             CA   TRAINED SPOTTER

            FLOODING IN TRABUCO CREEK WITH 5 RESCUES REPORTED IN
            TRABUCO CANYON. NO INJURIES REPORTED AT THIS TIME.

&&

PURPURA