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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
255 PM PDT THU AUG 21 2014

.SYNOPSIS...NIGHT AND MORNING LOW CLOUDS AND SLIGHTLY BELOW
NORMAL AFTERNOON HIGH TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND. WARMER TEMPERATURES ARE POSSIBLE INLAND BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...AS OF 02:45 PM PDT THURSDAY...CLOUDS HAVE CLEARED
BACK TO THE COAST THIS AFTERNOON. UNLIKE YESTERDAY THE SOUTHERLY
FLOW HAS WEAKENED ALLOWING EVEN THE NORTH BAY TO CLEAR OUT BY LATE
MORNING...SO THAT AFTER A COOL START IN THE 50S SANTA ROSA IS NOW UP
TO 80.

THE MARINE LAYER WILL STAY STEADY AROUND 2000 FEET TONIGHT
MAINTAINING A SIMILAR STRATUS PATTERN...WHILE A TROUGH BUILDS INTO
THE PACIFIC NORTHWEST SLIGHTLY COOLING TEMPERATURES TOMORROW. AS
THE TROUGH DIGS SOUTHEAST INTO THE GREAT BASIN FRIDAY NIGHT INTO
SATURDAY THE MARINE LAYER LOOKS TO DEEPEN LEADING TO DRIZZLE ALONG
THE COAST AND TEMPERATURES STAY SLIGHTLY BELOW NORMAL INTO THE
WEEKEND.

EARLY NEXT WEEK THE TROUGH SHIFTS EAST AS A RIDGE BUILDS JUST
OFFSHORE. THE GFS AND ECMWF AGREE THAT THE TROUGH WILL QUICKLY
EXPAND AND PROGRESS EASTWARD BY TUESDAY LEADING TO A WARMING
TREND. THE GEM IS A BIT SLOWER HOLDING OFF THE WARMING UNTIL
WEDNESDAY. 

&&

.AVIATION...AS OF 10:30 AM PDT THURSDAY...AS FORECAST, CLEARING
HAPPENED EARLIER TODAY ALTHOUGH STILL SEEING MVFR TO IFR CIGS
ACROSS NAPA/SONOMA WHICH SHOULD BURN OFF SHORTLY. LOOKING FOR VFR
FOR THE AFTERNOON INTO THE EARLY EVENING HOURS FOR ALL TERMINALS.
SEA BREEZE WINDS ALSO EXPECTED TO RAMP UP 20Z-02Z. MODELS IN GOOD
AGREEMENT FOR A LATE RETURN FOR MVFR CIGS FOR MOST AREAS TONIGHT.
MODERATE TO HIGH CONFIDENCE.

VICINITY OF KSFO...VFR THROUGH THE DAY WITH WINDS 280-300 GUSTING
UP TO AROUND 20 KT FROM 21Z TO 02Z. LATE RETURN OF STRATUS
EXPECTED TONIGHT -- POSSIBLY AFTER 11Z. HIGH CONFIDENCE THROUGH
02Z. MODERATE TO HIGH CONFIDENCE ON THE RETURN FOR TONIGHT.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...VFR THROUGH THE DAY WITH WINDS
240-280 UP TO 12 KT. RETURN OF MVFR CIGS AFTER 02Z ALTHOUGH
POSSIBLE THEY COULD BE LATER THAN THAT TIME. HIGH CONFIDENCE
THROUGH 0Z. MODERATE CONFIDENCE AFTER THAT.
&&

.MARINE...AS OF 2:23 AM PDT THURSDAY...GENERALLY TRANQUIL CONDITIONS
WILL CONTINUE THROUGH THE EVENING. BY SATURDAY THE SURFACE
PRESSURE GRADIENT IS EXPECTED TO INCREASE ...RESULTING IN
STRENGTHENING WINDS. A MODERATE PERIOD SOUTHERLY SWELL GENERATED
BY TROPICAL STORMS WILL MOVE INTO THE REGION LATER THIS WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PT REYES 10-60 NM FROM 11 PM
             SCA...SF BAY NORTH OF THE BAY BRIDGE UNTIL 11 PM

&&

$$

PUBLIC FORECAST: AC
AVIATION/MARINE: BELL

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