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000
FXUS66 KSGX 181633
AFDSGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
935 AM PDT SAT MAY 18 2013

.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY BUILD OVER THE EASTERN PACIFIC THROUGH
MONDAY...BRINGING DRIER AND WARMER CONDITIONS TO SOUTHERN CALIFORNIA
AS WELL AS A SHALLOWER MARINE LAYER.  A PERIOD OF LIGHT TO MODERATE
OFFSHORE WINDS WILL ALSO DEVELOP ALONG THE COASTAL FOOTHILLS SUNDAY
NIGHT INTO MONDAY MORNING...WITH LOCAL GUSTS UP TO 35 MPH POSSIBLE
IN THE FAVORED SPOTS.  ANOTHER TROUGH OF LOW PRESSURE WILL THEN MOVE
INTO THE PACIFIC NORTHWEST ON TUESDAY...DEEPENING ALONG THE WEST
COAST FOR THE REMAINDER FOR THE WORK WEEK.  THEREFORE...EXPECT A
GRADUAL COOLING TREND AND DEEPENING OF THE MARINE LAYER...WITH
LOCALLY GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

WATER VAPOR IMAGERY CONTINUES TO SHOW CALIFORNIA UNDER NORTHWESTERLY
FLOW ALOFT...AS A TROUGH SHIFTS TO THE EAST ACROSS THE GREAT BASIN
AND HIGH PRESSURE BUILDS OVER THE EASTERN PACIFIC.  AS A RESULT...A
GRADUAL DRYING AND WARMING TREND WILL DEVELOP OVER THE SOUTHLAND
STARTING TODAY.  HOWEVER...AREAS WEST OF THE MOUNTAINS ARE STILL
DEALING WITH SOME LINGERING LOW CLOUDS...WHICH APPEARS TO BE BACK
FILLING TOWARDS THE COAST THANKS TO THE EDDY CIRCULATION.  THIS WILL
MAKE FOR A CLOUDY START TO THE MORNING...WITH MOST LOCATIONS WITHIN
SIMILAR TO OR SLIGHTLY WARMER THAN WHERE THEY WERE AT THIS TIME
YESTERDAY MORNING.  ALTHOUGH THE 12Z KNKX SHOWS UP TO 5 DEGREES OF
COOLING THIS MORNING NEAR 850 MBS...THE MODELS ARE SUGGESTING A
DECENT WARM UP AT 850 MBS BY THIS AFTERNOON.  THEREFORE...THINK
TEMPERATURES TODAY WILL LIKELY BE SIMILAR TO YESTERDAY TO A FEW
DEGREES WARMER.

THIS RIDGE WILL CONTINUE TO BUILD OVER THE EASTERN PACIFIC THROUGH
MONDAY...WITH THE WARMING TREND CONTINUING.  AT THIS POINT IN
TIME...IT LOOKS AS THOUGH MONDAY WILL BE THE WARMEST DAY...WITH
INLAND AREAS SEEING TEMPERATURES 5 TO 12 DEGREES ABOVE NORMAL.
HOWEVER...A SHALLOW MARINE LAYER WILL HELP MODERATE TEMPERATURES
ALONG THE COAST.  A WEAK TO MODERATE OFFSHORE WIND EVENT WITH ALSO
BRIEFLY DEVELOP LATE SUNDAY NIGHT INTO MONDAY MORNING...AS A
DISTURBANCE PASSES BY TO THE EAST.  THEREFORE...EXCEPT SOME LOCAL
GUSTS UP TO 35 OR 40 MPH POSSIBLE IN THE FAVORED SPOTS ALONG THE
COASTAL FOOTHILLS.  HOWEVER...THESE WINDS DO NOT APPEAR STRONG
ENOUGH TO MAKE IT ALL THE WAY TO THE COAST.

A TROUGH OF LOW PRESSURE WILL THEN MOVE INTO THE PACIFIC NORTHWEST
ON TUESDAY...SQUASHING THE RIDGE ONCE AGAIN.  THEREFORE...EXPECT A
GRADUAL COOLING TREND TO START ACROSS THE SOUTHLAND...EVEN THOUGH
INLAND AREAS WILL STILL BE QUITE WARM.  A MORE SIGNIFICANT COOLING
TREND WILL DEVELOP ON WEDNESDAY THROUGH FRIDAY THOUGH...AS THIS
TROUGH DEEPENS OVER THE WEST.  THE MARINE LAYER WILL ALSO DEEPEN
DURING THIS TIME...WITH MORE EXTENSIVE LOW CLOUDS AND FOG POSSIBLE
EACH NIGHT.  IT MAY EVEN DEEPEN ENOUGH FOR SOME DRIZZLE WEST OF THE
MOUNTAINS THURSDAY NIGHT AND FRIDAY NIGHT...ALTHOUGH THE REAL
CHANCES OF PRECIPITATION WILL STAY WELL TO OUR NORTH.  THE ONSHORE
FLOW WILL STRENGTHEN AS WELL...WITH LOCALLY GUSTY WEST WINDS IN THE
MOUNTAINS AND DESERTS THESE DAYS.

&&

.AVIATION...
181526Z...COAST/VALLEYS...PATCHY STRATUS WITH VARIABLE BASES
1500-2500 FT MSL AND TOPS AROUND 3500 FT MSL...WILL CONTINUE TO
CLEAR OUT THROUGH 1800 UTC...WITH FEW-SCT CLDS 2500-3000 FT MSL
LINGERING AFTER 1800 UTC. 19/0200-0900 UTC...BKN-OVC STRATUS MOVING
INLAND 10-15 SM...WITH BASES 1000-1500 FT MSL AND TOPS 2000 FT MSL.
STRATUS LIKELY NOT REACHING KONT. CLEARING OF STRATUS 19/1500-1800
UTC.

MTNS/DESERTS...UNRESTRICTED VIS AND SKC THROUGH SUNDAY MORNING. W TO
NW WIND GUSTS OF 25-35 KT ALONG AND E OF MTN RIDGE-TOPS WILL
CONTINUE TO CREATE MOD-STG UDDFS.

&&

.MARINE...
A 3 FT/17-18 SECOND SOUTHWEST SWELL WILL ARRIVE TOMORROW AND
CONTINUE THROUGH WEDNESDAY...BRINGING ELEVATED SURF AND STRONG RIP
CURRENTS TO SOUTH AND SOUTHWEST FACING BEACHES.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...PALMER
AVIATION/MARINE...HARRISON