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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
432 AM PDT THU JUL 24 2014

.SYNOPSIS...MOSTLY CLEAR WITH A WARMING TREND TODAY THROUGH
SATURDAY WITH WEAK OFFSHORE FLOW IN THE HILLS. CONTINUED WARM AND
DRY INLAND OVER THE WEEKEND THROUGH EARLY NEXT WEEK WHILE MILD
WEATHER PERSISTS AT THE COAST WITH A RETURN OF COASTAL LOW CLOUDS
AND FOG.

&&

.DISCUSSION...AS OF 3:05 AM PDT THURSDAY...A FAIRLY STRONG
MID-SUMMER TROUGH IS CURRENTLY MOVING ONSHORE IN THE PACIFIC
NORTHWEST. THIS IS CAUSING A STRONG NORTHERLY GRADIENT TO DEVELOP
ALONG THE NORTHERN CALIFORNIA COAST WITH SFO-ACV CURRENTLY 6 MB.
THIS HAS SWEPT MOST OF THE LOW CLOUDS FROM THE OCEAN ALTHOUGH A
SHALLOW CLOUD DECK HAS BUMPED UP ALONG THE COASTLINE WITH HALF
MOON BAY CURRENTLY REPORTING A 600 FOOT CLOUD DECK AND 1100 FEET
AT KSFO. ANY LOW CLOUDS AND FOG ARE FORECAST TO QUICKLY MIX OUT
AFTER SUNRISE THIS MORNING AS DRIER AIR FILTER OVER THE REGION.
MAIN WEATHER STORY THE NEXT FEW DAYS WILL THEN BE SIGNIFICANT
WARMING...ESPECIALLY FOR INLAND AREAS AND THOSE THAT ARE FAVORED
BY LIGHT NORTH/NORTHEAST WINDS IN THE HILLS...SUCH AS THE NORTH
BAY VALLEYS.

ON WEDS HIGHS IN THE NORTH BAY WERE ONLY IN THE LOW 80S AND ARE
FORECAST TO WARM FROM THE UPPER 80S TO UPPER 90S FROM THIS
AFTERNOON THROUGH SATURDAY AS THE THERMAL TROUGH WILL SHIFT
TOWARDS THE COAST EACH MORNING WITH LIGHT OFFSHORE BREEZES IN THE
HILLS AND ONLY A WEAK AFTERNOON SEA-BREEZE. PLACES LIKE THE EAST
BAY VALLEYS WILL LIKELY SEE TEMPERATURES WARM ABOVE 100 DEGREES BY
FRIDAY AFTERNOON. FRIDAY LOOKS LIKE THE HOTTEST DAY AT THIS TIME
BUT ANY COOLING ON SATURDAY LOOKS TO BE SUBTLE...ON THE ORDER OF
ONLY A FEW DEGREES.

THE LONG RANGE FORECAST WILL FEATURE SEASONABLE WEATHER. A WEAK
UPPER LOW WELL OFF THE COAST WILL KEEP ONSHORE WINDS IN PLACE AND
WITH SST COOLING BACK TO NORMAL UNDER NORTHWEST WINDS EXPECT TO SEE
MORE WIDESPREAD COASTAL LOW CLOUDS AND FOG BY EARLY NEXT WEEK
WHILE INLAND AREAS WILL REMAIN WARM TO HOT AS THE FOUR CORNERS
HIGH EXPANDS WESTWARD OVER CALIFORNIA WITH ITS INFLUENCE BEING
FELT OVER THE CENTRAL VALLEY AND EASTERN SECTIONS OF THE GREATER
BAY AREA.

&&

.AVIATION...AS OF 04:30 AM PDT THURSDAY...STRONG NORTHERLY
GRADIENT THIS MORNING WITH SFO-ACV OVER 6 MB. THIS IS PREVENTING
MOST STRATUS DEVELOPMENT OFFSHORE HOWEVER ENOUGH HAS ADVECTED
THROUGH TO IMPACT SFO AND OAK. LOW CLOUDS TO BURN OFF SOMEWHAT
EARLY AS DRY AIR MOVES IN. ANY LOW CLOUDS TONIGHT LIKELY TO BE
PATCHY. 

VICINITY OF KSFO...MVFR THIS MORNING...BURN OFF BY AROUND 16Z.
MODERATE WEST WINDS IN THE AFTERNOON.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...PATCHY LOW CLOUDS MAY BRIEFLY IMPACT
MRY EARLY...OTHERWISE VFR. STRATUS POSSIBLE LATE TONIGHT.

&&

.MARINE...AS OF 3:05 AM PDT THURSDAY...NORTHWESTERLY WINDS WILL
INCREASE OVER THE COASTAL WATERS TODAY AS HIGH PRESSURE BUILDS
OVER THE EASTERN PACIFIC. THESE WINDS WILL RESULT IN CHOPPY SEAS
AND STEEP FRESH SWELL.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...MONTEREY BAY FROM 3 PM
             SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 3 PM
             SCA...PT ARENA TO PT REYES 10-60 NM
             SCA...PT REYES TO PIGEON PT 10-60 NM
             SCA...PT ARENA TO PT REYES 0-10 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 REYES TO PIGEON PT 0-10 NM UNTIL 9 AM

&&

$$

PUBLIC FORECAST: RWW
AVIATION/MARINE: AC

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