Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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000
FXUS66 KMTR 272142
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
242 PM PDT FRI MAR 27 2015

.SYNOPSIS...ONSHORE FLOW WILL WEAKEN ON SATURDAY... AND RESULT
IN MOSTLY CLEAR SKIES AND WARMING TEMPERATURES FOR SUNDAY. COOLER
TEMPERATURES ARE THEN EXPECTED BEGINNING ON MONDAY. DRY WEATHER TO
PERSIST THROUGH THE FORECAST PERIOD.

&&

.DISCUSSION...AS OF 02:42 PM PDT FRIDAY...DRY WEATHER WILL
CONTINUE THROUGH THE NEXT SEVEN DAYS WITH SLIGHTLY ABOVE NORMAL TEMPERATURES.

INTERESTING VISIBLE SATELLITE PICTURE THIS AFTERNOON SHOWING THAT
THE MORNING LOW CLOUDS/FOG HAS HUNG ALONG THE MAJORITY OF THE
COASTLINE THIS AFTERNOON. AS ONE WOULD SUSPECT THE LINGERING
CLOUDS HAS ADVERSELY IMPACTED AFTERNOON TEMPERATURES. LOCATIONS
ALONG THE IMMEDIATE COASTLINE STILL STUCK IN THE CLOUDS ARE
STRUGGLING TO EVEN REACH THE 60S. AWAY FROM THE COAST
HOWEVER...TEMPERATURES DID WARM NICELY INTO THE 70S AND 80S.

SHORT TERM(TONIGHT-MONDAY)...
ONCE THE SUN SETS EXPECT THE COASTAL STRATUS TO COME BACK IN
LOCALLY. THE UPSTREAM COLD FRONT SEEN ON VIS SATELLITE WILL
CONTINUE TO APPROACH THE BAY AREA AND GRADUALLY DISSIPATE BY EARLY
SATURDAY. THROUGH MONDAY...MORNINGS MAY START OF WITH SOME PATCHY
CLOUDS/FOG BUT THE AFTERNOONS SHOULD BE PLEASANT WITH TEMPS ABOVE
NORMAL. INTERIOR LOCATIONS WILL BE A LITTLE COOLER THAN TODAY AS
THE PASSING WEAK FRONT BRINGS IN COOLER AIR...ESPECIALLY SATURDAY. TEMPS
WILL BE IN THE 60S AND 70S AT THE COAST AND 70S AND 80S INLAND. NO
PRECIP EXPECTED AS A WEAK RIDGE RE-BUILDS ON MONDAY.

LONG TERM(TUESDAY-FRIDAY)...
BROAD UPPER LEVEL TROUGH WILL MOVE INTO NORCAL EARLY NEXT ALLOWING
FOR A DROP IN AFTERNOON TEMPERATURES TUESDAY AND WEDNESDAY. SOME OF THE
MODEL GUIDANCE TRIES TO BRING SOME LIGHT PRECIP INTO THE FAR
NORTH BAY ON TUESDAY...BUT THINK THERE IS A BETTER CHANCE FARTHER
NORTH...ESP NEAR THE CA/OR BORDER. FOR NOW...STILL NO MENTION OF
PRECIP IN THE FORECAST. UPPER LEVEL RIDING RETURNS FOR THURSDAY
AND FRIDAY WITH A SLIGHT WARMING TREND.



&&

.AVIATION...AS OF 11:10 AM PDT FRIDAY... A SHALLOW STRATUS DECK
PUSHED ONSHORE OVERNIGHT WHICH LED TO POCKETS OF LIFR VISBYS AND
CIGS ALONG THE COAST AND THROUGH INLAND VALLEYS THROUGH THIS
MORNING. THAT INITIAL OVERNIGHT PUSH INLAND HAS NOW RETREATED THIS
MORNING.

ONSHORE FLOW IS EXPECTED TO STRENGTHEN AND BECOME BREEZY/GUSTY
THROUGH THE DAY AS A WEAK SYSTEM PASSES TO A NORTH AND PRESSURE
GRADIENTS TIGHTEN. PEAK WIND GUSTS 20-30KT POSSIBLE. GOES-W CLOUD
THICKNESS IMAGERY SHOWS THE STRATUS DECK ALONG CALI SHORELINE
THICKENING FROM 300-500FT TO OVER 2000FT IN THE VICINITY OF PT
REYES AND THE BAY AREA. LATEST VISIBLE SATELLITE IMAGERY SHOWS
THIS DEEPENING LAYER MAY MAKE ANOTHER PUSH ONSHORE WITH STRONGER
ONSHORE FLOW ALOFT... AT THE SAME TIME THAT THE SHALLOWER LEVEL
LAYER IS RETREATING. THUS... CAN NOT RULE OUT MVFR CIGS RETURNING
INTO THE BAY AREA PRIOR TO 00Z.

LATEST WRF SUGGESTS AN EARLY RETURN OF STRATUS...AROUND 00Z...IN A
SUMMER LIKE SCENARIO. CONFIDENCE ON THIS TIMING IS LOW TO
MODERATE. HOWEVER EXPECT STRATUS TO RETURN NO LATER THAN 04Z FOR A
MAJORITY OF TAF LOCATIONS (EXCLUDING KLVK AND POSSIBLY KSJC).

VICINITY OF KSFO... BREEZY ONSHORE FLOW TODAY WITH PEAK GUSTS
25-30 KT. VFR CIGS THROUGH 00Z... THEN DETERIORATING CIGS. SLIGHT
CHANCE OF EARLY STRATUS RETURN PRIOR TO 00Z.

CONFIDENCE IS LOW TO MODERATE.

SFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS... ONSHORE FLOW WITH VFR CONDS INTO
THE AFTERNOON... THEN DETERIORATING CIGS BEGINNING AROUND 00Z.
SLIGHT CHANCE OF EARLY STRATUS RETURN PRIOR TO 00Z.

CONFIDENCE IS LOW TO MODERATE.

&&

.MARINE...AS OF 02:13 PM PDT FRIDAY...NORTHWEST WINDS ARE FORECAST
TO FURTHER STRENGTHEN OVERNIGHT AND PERSIST INTO THE SMALL CRAFT
ADVISORY RANGE THROUGH THE WEEKEND AND POSSIBLY INTO EARLY NEXT
WEEK. STRONG WINDS WILL GENERATE STEEP FRESH SWELL THROUGH THE
WEEKEND. MIXED SWELL THROUGH THE PERIOD WITH A DOMINANT WEST
SWELL.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PT REYES 10-60 NM
             SCA...PT REYES TO PIGEON PT 10-60 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             SCA...PIGEON PT TO PT PINOS 10-60 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
             SCA...PT ARENA TO PT REYES 0-10 NM
             SCA...PT REYES TO PIGEON PT 0-10 NM
             SCA...ROUGH BAR ADVISORY FOR SF BAR
             SCA...SF BAY NORTH OF THE BAY BRIDGE UNTIL 8 PM
             SCA...SF BAY SOUTH OF THE BAY BRIDGE UNTIL 8 PM

&&

$$

PUBLIC FORECAST: MM
AVIATION/MARINE: DRP

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