Special Weather Statement

Special Weather Statement
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
110 PM PST THU DEC 10 2009

CAZ042-043-048-050-055>058-060>062-111200-
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-
110 PM PST THU DEC 10 2009

...WET WEATHER MOVING BACK INTO SOUTHERN CALIFORNIA THIS WEEKEND...

A STRING OF DISTURBANCES OVER THE EAST PACIFIC WILL BE MOVING
THROUGH SOUTHERN CALIFORNIA BEGINNING ON FRIDAY AND CONTINUING
THROUGH SUNDAY. PERIODS OF RAIN...AND SNOW AT HIGHER ELEVATIONS IN
THE MOUNTAINS ARE EXPECTED. ISOLATED THUNDERSTORMS WILL BE POSSIBLE
AS WELL.

THE FIRST SYSTEM WILL BRING LIGHT TO LOCALLY MODERATE RAIN SHOWERS
FRIDAY MORNING. AN ISOLATED THUNDERSTORM OR TWO IS POSSIBLE EARLY IN
THE MORNING WITH LOCALLY BRIEF HEAVY RAIN. THIS WILL BE FOLLOWED BY
ANOTHER PERIOD OF LIGHT TO MODERATE RAIN ON SATURDAY MORNING. ONE
FINAL ROUND OF MODERATE TO LOCALLY HEAVY RAIN AND SNOW IS POSSIBLE
LATE SATURDAY INTO SUNDAY MORNING. IN BETWEEN EACH SYSTEM...LIGHT
SHOWERS MAY LINGER NEAR THE FOOTHILLS AND MOUNTAINS DUE TO CONTINUED
MOIST WESTERLY FLOW.

TOTAL RAINFALL AMOUNTS FOR THE ENTIRE EVENT THROUGH SUNDAY SHOULD
GENERALLY BE IN THE RANGE OF 0.75 TO 1.75 INCHES FOR THE COAST AND
VALLEYS...AND 2.00 TO LOCALLY 4.00 INCHES ON THE FOOTHILLS AND
COASTAL SLOPES OF THE MOUNTAINS. THE BIGGEST TOTALS SHOULD BE IN THE
SAN BERNARDINO MOUNTAINS. LOCALLY HEAVIER AMOUNTS ARE POSSIBLE WHERE
THUNDERSTORMS DEVELOP. SNOW LEVELS WILL INITIALLY BE QUITE HIGH ON
FRIDAY...NEAR 7000 FEET...BUT SHOULD FALL TO AROUND 5500 FEET OVER
THE SAN BERNARDINOS AND 6500 FEET OVER THE SAN JACINTOS BY SUNDAY
MORNING...WHERE UP SIX INCHES OF SNOW COULD ACCUMULATE BY SUNDAY
NIGHT. LITTLE SNOW ACCUMULATION IS EXPECTED ON THE SAN DIEGO COUNTY
MOUNTAINS. IN THE DESERTS...GENERALLY ONE HALF INCH OF RAIN OR LESS
IS EXPECTED.

RAINFALL OF SEVERAL INCHES COULD CAUSE RIVERS TO RISE ENOUGH TO
FLOOD LOW-LYING...TYPICALLY FLOOD PRONE AREAS IN SAN DIEGO COUNTY.
EVEN THOUGH WIDESPREAD HEAVY RAIN IS NOT EXPECTED FOR SAN DIEGO
COUNTY AT THIS TIME...ISOLATED CONVECTION...OR A SLIGHT SHIFT IN THE
STORM TRACK WOULD MAKE IT MORE LIKELY. OF MAIN CONCERN WOULD BE THE
SOUTH COAST NEAR THE TIJUANA RIVER...AND THE SAN DIEGO RIVER...WHERE
LOW-WATER CROSSINGS WOULD NEED TO BE BARRICADED.

HEAVY RAINFALL ON RECENT BURN AREAS COULD RESULT IN LIFE-THREATENING
DEBRIS FLOWS. A FLASH FLOOD WATCH MAY BE NEEDED IN THESE AREAS BY
SATURDAY.

PERSONS LIVING IN AND CLOSE TO RECENTLY BURNED AREAS OR IN LOW-LYING
AREAS SUBJECT TO RIVER AND STREAM FLOODING SHOULD KEEP ABREAST OF
LATER FORECASTS.

STAYED TUNED FOR UPDATES ON THIS DEVELOPING WEATHER EVENT. LISTEN TO
NOAA WEATHER RADIO OR VISIT OUR WEBSITE AT WEATHER.GOV/SANDIEGO FOR
THE LATEST UPDATES OF FORECASTS AND WARNINGS.

$$