FXUS66 KSGX 120528
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 PM PST FRI DEC 11 2009
.SYNOPSIS...A SERIES OF FAST MOVING STORMS WILL BRING CLOUDS AND
OCCASIONAL SHOWERS THROUGH SATURDAY...THEN A COLD FRONT WILL BRING A
PERIOD OF STEADY RAIN AND SHOWERS WITH MOUNTAIN SNOW LATE SATURDAY
NIGHT THROUGH EARLY SUNDAY MORNING. DRY AND WARMER WEATHER NEXT WEEK
AS WEAK HIGH PRESSURE BUILDS OVER THE SOUTHWEST.
&&
.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
LIGHT RAIN AND DRIZZLE CONTINUED OVER MUCH OF EXTREME SOUTHWESTERN
CALIFORNIA THROUGH THE AFTERNOON. PRECIP AMOUNTS SO FAR HAVE RANGED
FROM LESS THAN A TENTH OF AN INCH IN SOME COASTAL LOCATIONS TO
GREATER THAN AN INCH IN SOME LOCATIONS IN THE SAN BERNARDINO MTNS.
AN AREA OF EMBEDDED SHOWERS...ASSOCIATED WITH A FAST-MOVING UPPER
LEVEL DISTURBANCE...MOVED ACROSS THE AREA AT ABOUT 25 MPH...AND WILL
HAVE MOVED EAST BY MIDNIGHT. EXPECT ISOLATED SHOWERS TO CONTINUE
THROUGH TONIGHT WITH AN INCREASE IN ACTIVITY LATE TONIGHT INTO
SATURDAY MORNING AS ANOTHER FAST-MOVING UPPER LEVEL DISTURBANCE
MOVES THROUGH. THE SNOW LEVEL SHOULD HOVER AROUND 6500-7000 FEET.
PRECIP WILL LIKELY BE A RAIN/SNOW MIX IN THE BIG BEAR AREA.
SHOWERS WILL THEN DECREASE THROUGH LATE SATURDAY MORNING...WITH ONLY
A FEW LINGERING SHOWERS NEAR THE MOUNTAINS AND FOOTHILLS BY SATURDAY
AFTERNOON. CONTINUED COOL AND MOSTLY CLOUDY WITH HIGH TEMPERATURES
BELOW SEASONAL AVERAGES THROUGH THE WEEKEND.
THE BEST CHANCE FOR WIDESPREAD LIGHT TO MODERATE RAIN IS EXPECTED
LATE SATURDAY NIGHT AND EARLY SUNDAY MORNING AS A STRONGER SYSTEM
MOVES INTO THE WEST COAST. A BRIEF PERIOD OF LOCALLY HEAVY RAIN IS
POSSIBLE AS THE FRONT MOVES THROUGH LATE SATURDAY NIGHT INTO EARLY
SUNDAY MORNING. SNOW LEVEL WILL FALL TO AROUND 5500 FT IN THE SAN
BERNARDINO MTNS...6500 FT IN THE SAN DIEGO MTNS...BY LATE SATURDAY
NIGHT OR EARLY SUNDAY MORNING. GRADUAL DRYING IS EXPECTED TO BEGIN
SUNDAY AFTERNOON WITH ONLY A FEW LINGERING SHOWERS INLAND.
ESTIMATED RAINFALL TOTAL TODAY THROUGH SUNDAY ARE FOR BETWEEN 0.50
TO 1.50 INCHES FOR THE COAST AND VALLEYS...AND 1.50 TO 3.00 INCHES
IN THE MOUNTAINS WITH LOCAL AMOUNTS UP TO 4.00 INCHES IN THE SAN
BERNARDINO MOUNTAINS. RAINFALL AMOUNTS DECREASING FROM NORTH TO
SOUTH. SIX TO EIGHT INCHES OF SNOW COULD ACCUMULATE BY SUNDAY AT
RESORT LEVELS IN THE SAN BERNARDINO MOUNTAINS. LOCAL AMOUNTS TO 12
INCHES OR MORE ARE POSSIBLE AT HIGHER ELEVATIONS IN THE WILDERNESS
AREAS. LITTLE TO NO SNOW ACCUMULATION IS EXPECTED IN THE SAN DIEGO
COUNTY MOUNTAINS. IN THE DESERTS...GENERALLY ONE THIRD OF AN INCH OF
RAIN OR LESS IS EXPECTED.
MEDIUM RANGE MODELS CONTINUE TO INDICATE RIDGING WILL OCCUR OVER
SOUTHERN CALIFORNIA BEHIND THIS SYSTEM WHICH SHOULD BRING CLEARING
OVERNIGHT SUNDAY NIGHT INTO MONDAY AND DRY WEATHER THROUGH NEXT
WEEK. TEMPERATURES SHOULD RETURN TO AROUND SEASONAL AVERAGES NEXT
WEEK AS WELL.
&&
.AVIATION...
120500Z...FROM THE MTNS W TO THE COAST...SCATTERED SHOWERS WILL
CONTINUE OVERNIGHT...INCREASING SOMEWHAT FROM THE NORTHWEST TOWARDS
MORNING. CEILINGS WILL BE HIGHLY VARIABLE AT ANY ONE
LOCATION...AVERAGING BETWEEN 1500 AND 2500 FT MSL...BUT VARYING
BETWEEN A FEW HUNDRED FEET AGL...EVEN NEAR THE COAST...TO OVER 3000
FT MSL. VIS WILL VARY AS WELL...BETWEEN 1 AND 7 MILES...AND HIGHER
TERRAIN WILL BE OBSCURED AT TIMES. CONDITIONS WILL IMPROVE
GRADUALLY AROUND MIDDAY SAT...THEN RAIN WILL AGAIN INCREASE SAT
NIGHT.
IN THE DESERTS...PRECIP WILL BE MORE ISOLATED...AND CIGS WILL MOSTLY
STAY ABOVE FL040.
&&
.MARINE...
A PERIOD OF STRONG GUSTY WINDS WILL BE POSSIBLE SATURDAY NIGHT WITH
THE PASSAGE OF A COLD FRONT. WINDS WILL GENERALLY BE 15-20 KT...BUT
THEY COULD BE AS MUCH AS 25 KT FOR A SHORT TIME PERIOD...RESULTING
IN HAZARDOUS BOATING CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...PG
AVIATION/MARINE...MAXWELL
