FXUS66 KSGX 281048 CCA
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
300 AM PST SAT NOV 28 2009
.SYNOPSIS...UPPER LEVEL LOW SLOWLY DIVING SOUTH THROUGH THE STATE.
IT WILL BE OVER SOUTHERN CALIFORNIA LATER THIS MORNING THROUGH THIS
AFTERNOON. SCATTERED SHOWERS WITH A SLIGHT CHANCE FOR THUNDERSTORMS
TODAY WILL DECREASE THIS EVENING. MOISTURE WILL ROTATE AROUND THE
LOW AS IT DROPS SOUTH AND SHOWERS MAY CONTINUE MAINLY OVER THE
MOUNTAINS THROUGH SUNDAY AFTERNOON. THE SNOW LEVEL WILL DROP TO
AROUND 4500 FEET AND LOCALLY LOWER WITH AROUND 3 TO 6 INCHES OF SNOW
IN THE HIGHER ELEVATIONS. GUSTY NORTHEAST WINDS WILL DEVELOP SUNDAY
THROUGH MONDAY MORNING WITH A WEAK FLOW MONDAY AFTERNOON THROUGH
FRIDAY. HIGH PRESSURE ALOFT MOVES OVER LATE SUNDAY THROUGH
TUESDAY...WEAKENING WEDNESDAY...INCREASING THURSDAY AND FRIDAY.
&&
.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
MARINE LAYER WENT THROUGH THE ROOF AND GAVE RISE TO SOME RAIN IN THE
COASTAL BASIN TO THE COASTAL SLOPES LAST NIGHT THROUGH EARLY THIS
MORNING. SCATTERED SHOWERS ASSOCIATED WITH THE UPPER LEVEL LOW
PRESSURE SYSTEM WERE SLOWLY MOVING TOWARD THE AREA. THEY WERE JUST
MOVING INTO THE UPPER DESERTS EARLY THIS MORNING. LOCALLY BREEZY TO
WINDY THIS MORNING. VERY COLD AIR ALOFT WILL MAKE FOR AN UNSTABLE
AIRMASS WITH THE POSSIBILITY FOR THUNDERSTORMS DEVELOPING TODAY. THE
SNOW LEVEL WILL DROP TO 5000 FT AND LOCALLY LOWER THIS MORNING AND
NEAR 4000 FT TONIGHT. AN INCH OR TWO POSSIBLE AROUND 5000 FT WITH
AROUND 5 INCHES IN THE SAN BERNARDINO MOUNTAINS ABOVE 6000 FT. THE
UPPER LEVEL LOW IS FORECAST TO DROP SOUTH OF THE BORDER LATE TONIGHT
THROUGH SUNDAY AND MOVE EAST SUNDAY NIGHT. MOISTURE ROTATING AROUND
THE LOW MAY CONTINUE SHOWERS MAINLY OVER THE MOUNTAINS THROUGH
SUNDAY. HIGH PRESSURE ALOFT WILL MOVE OVER LATE SUNDAY THROUGH
MONDAY WITH LITTLE CHANGE TUESDAY. AN OFFSHORE FLOW AT THE SURFACE
WITH NORTHEAST WINDS ALOFT WILL DEVELOP SUNDAY WITH THE STRONGEST
NORTHEAST WINDS EXPECTED SUNDAY NIGHT THROUGH MONDAY MORNING OVER
THE MOUNTAINS AND INLAND VALLEYS. A WEAK FLOW MONDAY AFTERNOON WILL
CONTINUE THROUGH FRIDAY. HIGH PRESSURE ALOFT WEAKENS WEDNESDAY. A
WEAK SYSTEM MAY MOVE THROUGH WEDNESDAY. HIGH PRESSURE ALOFT MOVES
OVER THURSDAY AND FRIDAY. COLDER TODAY...A BIT WARMER SUNDAY AND
WARMER MONDAY THROUGH TUESDAY...COOLER WEDNESDAY...THEN WARMER
THURSDAY THROUGH FRIDAY.
&&
.AVIATION...
280945Z...WIDESPREAD CLOUDS WITH BASES BETWEEN 2500-3500 FT MSL WILL
CONTINUE THROUGH THIS AFTERNOON. SHOWER ACTIVITY WILL INCREASE
THROUGH THE MORNING AS A LOW PRESSURE SYSTEM APPROACHES FROM THE
NORTH AND CONTINUE THROUGH THIS EVENING. ISOLATED THUNDERSTORMS ARE
ALSO POSSIBLE...MAINLY IN SAN DIEGO COUNTY. LOWER CIGS AND VSBY ARE
POSSIBLE IN HEAVIER SHOWERS. WINDS WILL INCREASE THROUGH THIS THE
MORNING WITH MOUNTAIN WAVE...ROTOR ACTIVITY AND BLOWING DUST IN THE
DESERTS. CLEARING WILL BEGIN LATE THIS AFTERNOON WITH WINDS
SUBSIDING AFTER 00Z. CHANCE OF SHOWERS WILL CONTINUE IN THE SAN
BERNARDINO COUNTY DESERTS AND MOUNTAINS THROUGH SUNDAY MORNING.
&&
.MARINE...
A LONG PERIOD 10 FT NW SWELL IS EXPECTED TO BUILD THROUGH
SATURDAY...PEAK SATURDAY EVENING...THEN DECREASE THROUGH SUNDAY.
THIS WILL BRING HIGH SURF AND DANGEROUS RIP CURRENTS TO THE BEACHES
THROUGH SUNDAY MORNING. COMBINED SEAS WILL BE AS HIGH AS 13 FEET IN
THE OUTER WATERS...AND UP TO 10 FEET IN THE INNER WATERS. SURF
HEIGHTS WILL BE 4 TO 7 FEET WITH SETS TO 9 FEET. OCCASIONAL SETS TO
11 FEET ARE POSSIBLE SOUTH OF DEL MAR.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WINTER WEATHER ADVISORY FOR THE SAN BERNARDINO MOUNTAINS UNTIL
3 PM SATURDAY.
HIGH SURF ADVISORY UNTIL 2 PM PST SUNDAY FOR ORANGE AND SAN
DIEGO COUNTY COASTAL AREAS.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS TO MIDNIGHT FOR THE
INNER WATERS AND UNTIL 8 AM PST SUNDAY FOR THE OUTER WATERS.
&&
$$
PUBLIC...WHITLOW
AVIATION/MARINE...SS
