Area Forecast Discussion
Issued by NWS San Diego, CA

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000
FXUS66 KSGX 281124
AFDSGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
330 AM PST FRI NOV 28 2014

.SYNOPSIS...
ONSHORE FLOW DEVELOPS TODAY FOR SOME COOLING WEST OF THE MOUNTAINS.
LOW CLOUDS AND FOG WILL RETURN TO THE COASTAL AREAS TONIGHT. THE
COOLING TREND WILL CONTINUE INTO THE WEEKEND AS THE UPPER RIDGE
BREAKS DOWN AND A TROUGH OF LOW PRESSURE DIGS OFF THE WEST COAST. A
WEAK WAVE MAY BRING DRIZZLE OR LIGHT RAIN ON SUNDAY. A PACIFIC STORM
IS STILL EXPECTED TO IMPACT THE REGION WITH WIDESPREAD RAIN AND HIGH
ELEVATION MOUNTAIN SNOW BY THE MIDDLE OF NEXT WEEK...BUT DETAILS ARE
STILL UNCERTAIN.

&&

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

SKIES WERE CLEAR OVER THE REGION THIS MORNING AND SURFACE PRESSURE
GRADIENTS WERE TRENDING ONSHORE. THE UPPER LEVEL RIDGE OF HIGH
PRESSURE WILL SHIFT EAST AND WEAKEN TODAY INTO THE WEEKEND WITH
ONSHORE FLOW RETURNING. THIS WILL BRING GRADUAL COOLING EACH DAY.
LOW CLOUDS AND FOG WILL RETURN TO THE COASTAL AREAS TONIGHT. A FEW
PATCHES OF DENSE FOG ARE POSSIBLE ON THE COASTAL MESAS AS LOW CLOUDS
MOVE IN...BUT HI-RES MODELS ADVERTISING A COASTAL EDDY DEVELOPING
TONIGHT SO DO NOT EXPECT FOG TO LAST LONG AS THE MARINE LAYER SHOULD
DEEPEN FAIRLY QUICKLY.

A WEAK SHORT WAVE WILL MOVE THROUGH ON SUNDAY. THIS WILL HELP DEEPEN
THE MARINE LAYER FURTHER WITH LOW CLOUDS SPREADING INTO THE INLAND
VALLEYS SAT NIGHT/SUN. SOME DRIZZLE IS POSSIBLE WEST OF THE
MOUNTAINS BY SUN MORNING AS THE MARINE LAYER DEEPENS...AND SHOWERS
ARE POSSIBLE DURING THE DAY SUNDAY AS THE WAVE MOVES THROUGH. ANY
MEASURABLE RAINFALL WILL BE LIMITED TO A COUPLE HUNDREDTHS OF AN
INCH. MODEST WARMING AND DRYING OCCURS MONDAY AS A WEAK UPPER LEVEL
SHORT WAVE RIDGE MOVES OVER.

DETAILS ON THE MIDWEEK STORM ARE STILL UP IN THE AIR. WHILE THE EC
HAS COME INTO BETTER ALIGNMENT WITH THE GFS ON THE TRACK AND TIMING
OF THE SYSTEM...IT IS STILL QUITE A BIT SLOWER AND DRIER THAN THE
GFS. THE 00Z AND 06Z GFS BOTH HAVE QUITE THE PLUME OF SUBTROPICAL
MOISTURE AIMED DIRECTLY AT SOUTHERN CALIFORNIA...WITH PW APPROACHING
1.6 INCHES ALONG THE COAST ON TUE. DUE TO INCONSISTENCIES BETWEEN
MODELS AND MODEL RUNS CONFIDENCE IS STILL SOMEWHAT LOW...ESPECIALLY
REGARDING RAINFALL AMOUNTS. AT THIS TIME IT LOOKS LIKE BEST CHANCES
FOR PRECIP WILL BE EARLY TUE MORNING THROUGH TUE EVENING...THOUGH
THAT IS STILL SUBJECT TO CHANGE. SHOWERS WILL LINGER INTO WEDNESDAY
AND POSSIBLY EVEN THURSDAY AS WE REMAIN UNDER CYCLONIC FLOW WITH A
DEEP MOIST BOUNDARY LAYER IN PLACE. SINCE WE WILL BE UNDER
RELATIVELY WARM SOUTHWEST FLOW WITH THIS SYSTEM...SNOW LEVELS WILL
BE RATHER HIGH...GENERALLY AROUND 7500 TO 8500 FT.

&&

.AVIATION...
281000Z...VFR CONDITIONS WITH FEW/SCT HIGH CLOUDS THROUGH THIS
EVENING. LOW CLOUDS...WITH BASES AROUND 500 FT MSL AND TOPS NEAR
1000 FT MSL...WILL SLOWLY DEVELOP ALONG THE COAST SATURDAY MORNING.
VISIBILITY OF 2-4 SM BR WILL BE POSSIBLE WHERE STRATUS NEARS COASTAL
MESAS.

&&

.MARINE...
200 AM...NO HAZARDOUS MARINE WEATHER FRIDAY AND SATURDAY. A FEW
LIGHT SHOWERS ARE POSSIBLE SUNDAY AND TUESDAY.

&&

.BEACHES...
200 AM...AN ELEVATED W-NW SWELL WILL CREATE ABOVE NORMAL SURF OF 4-6
FEET ALONG WESTERLY-FACING BEACHES TODAY THROUGH SATURDAY. HIGHER
SETS TO 7 FEET ARE LIKELY IN SOUTHERN SAN DIEGO COUNTY. THE SWELL
AND SURF WILL DECREASE SATURDAY NIGHT. A BEACH HAZARDS STATEMENT
REMAINS IN EFFECT FOR ELEVATED SURF AND A HIGH RIP CURRENT RISK
TODAY AND SATURDAY.


&&

.FIRE WEATHER...
EXPECT SOME IMPROVEMENT IN HUMIDITY TODAY ALONG THE COASTAL STRIP AS
ONSHORE FLOW RETURNS. MINIMUM RH WILL REMAIN BELOW IN THE UPPER
SINGLE DIGITS AND LOW TEENS INLAND. HUMIDITY WILL GRADUALLY IMPROVE
THROUGH THE WEEKEND AS ONSHORE FLOW STRAIGHTENS AND THE MARINE LAYER
DEEPENS.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...BEACH HAZARDS STATEMENT FROM 6 AM PST FRIDAY THROUGH SATURDAY
     AFTERNOON FOR THE BEACHES IN THE ORANGE COUNTY COASTAL
     AREAS...SAN DIEGO COUNTY COASTAL AREAS.

PZ...NONE.

&&

$$

PUBLIC/FIRE WEATHER...SS
AVIATION/MARINE...JJT




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