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

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000
FXUS66 KMTR 120549
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
949 PM PST THU FEB 11 2016

.SYNOPSIS...DRY WEATHER WILL CONTINUE THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. COOLER CONDITIONS ARE FORECAST FOR FRIDAY AND
SATURDAY...WITH WARMING THEN EXPECTED FOR SUNDAY AND MONDAY.
LARGE LONG-PERIOD WESTERLY SWELL WILL CONTINUE TO IMPACT THE
COAST THROUGH SATURDAY...CREATING HAZARDOUS CONDITIONS AT AREA
BEACHES...INCLUDING SNEAKER WAVES.

&&

.DISCUSSION...AS OF 8:50 PM PST THURSDAY...TODAY WAS ANOTHER WARM
DAY ACROSS THE REGION WITH HIGH TEMPERATURES ANYWHERE FROM 5 TO 15
DEGREES ABOVE AVERAGE. TWO CLIMATE STATIONS ACHIEVED RECORD HIGH
TEMPS FOR THE DATE...KING CITY (80) AND THE OAKLAND AIRPORT (74).

EVENING SATELLITE IMAGERY SHOWS A WEATHER SYSTEM APPROACHING THE
COAST OF THE PACIFIC NORTHWEST. THE UPPER RIDGE CENTERED OVER THE
WESTERN CONUS WILL DEFLECT THIS SYSTEM AND ITS PRECIP WELL TO OUR
NORTH. HOWEVER...THERE WILL BE A WEAKENING OF THE UPPER RIDGE OVER
THE NEXT TWO DAYS AS WELL AS THE DEVELOPMENT OF LIGHT ONSHORE
FLOW. THE RESULT WILL BE COOLER CONDITIONS ON FRIDAY AND
SATURDAY...ALONG WITH AREAS OF LOW CLOUDS AND FOG NEAR THE COAST.
THE PRIMARY FORECAST CONCERN IN THE SHORT-TERM IS HOW FAR INLAND
THE LOW CLOUDS/FOG WILL DEVELOP OVERNIGHT TONIGHT AND AGAIN FRIDAY
NIGHT. SURFACE PRESSURE GRADIENTS FROM THE COAST TO THE CENTRAL
VALLEY HAVE RECENTLY TURNED WEAK ONSHORE WHICH SHOULD MEAN AT
LEAST LOCAL INLAND DEVELOPMENT OF FOG/LOW CLOUDS OVERNIGHT.
BASED ON THE BOUNDARY LAYER RH FORECAST FROM BOTH THE WRF AND NAM
MODELS...NIGHT AND MORNING FOG AND LOW CLOUDS SHOULD MOSTLY BE
CONFINED TO AREAS NEAR THE OCEAN AND LOCALLY AROUND SF BAY. PATCHY
DENSE FOG IS POSSIBLE AS WELL.

BY LATE SATURDAY THE UPPER RIDGE IS FORECAST TO REDEVELOP JUST
OFFSHORE ALONG 130W. AT THE SAME TIME A SURFACE RIDGE WILL
DEVELOP ACROSS OREGON...AND THEN SE INTO NEVADA BY LATE SATURDAY
NIGHT. THESE DEVELOPMENTS WILL RESULT IN BRISK NORTH TO NORTHEAST
WINDS IN THE HILLS FROM LATE SATURDAY NIGHT INTO SUNDAY NIGHT.
OFFSHORE WINDS WILL CLEAR OUT ANY REMAINING COASTAL FOG AND LOW
CLOUDS BY LATE SATURDAY AND ALSO BRING ABOUT A WARMING TREND FROM
SUNDAY INTO MONDAY. OUR REGION COULD SEE RECORD WARM HIGH
TEMPERATURES ONCE AGAIN BY MONDAY.

THE MEDIUM RANGE MODELS ARE COMING INTO RELATIVELY GOOD AGREEMENT
CONCERNING THE POSSIBILITY OF RAIN BY THE MIDDLE PART OF NEXT
WEEK. THE GFS...EURO...AND CANADIAN ALL SHOW A SYSTEM FINALLY
BREAKING THROUGH TO THE CALIFORNIA COAST BY LATE WEDNESDAY INTO
THURSDAY OF NEXT WEEK. THIS IS STILL NEARLY A WEEK OUT AND COULD
VERY WELL CHANGE...BUT ITS ENCOURAGING TO SEE GOOD OVERALL MODEL
AGREEMENT.

&&

.AVIATION...AS OF 9:49 PM PST THURSDAY...FOR 06Z TAFS. HIGH CLOUDS
INLAND WITH A FOG BANK OVER THE OCEAN IMPACTING KMRY AND KSNS AS
WELL AS KWVI AND KHAF. GIVEN SHALLOW LAYER AND HIGH PRESSURE ALOFT
DONT BELIEVE THE FOG LAYER WILL IMPACT BAY AREA TERMINALS OVERNIGHT
INTO FRIDAY MORNING.

VICINITY OF KSFO...WINDS FINALLY SHIFTED WESTERLY THIS EVENING AND
WILL GRADUALLY DECREASE OVERNIGHT. AT THIS POINT NOT EXPECTING LOW
CIGS OR FOG TO IMPACT TERMINAL WITH HIGH CLOUDS CONTINUING OVERHEAD.

SFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...FOGBANK OVER THE OCEAN HAS MOVED
ONSHORE AROUND MONTEREY BAY FROM KWVI TO KMRY AND OVER TO KSNS
WITH KHAF REPORTING 1/4 MILE AS WELL. BASES ARE SHALLOW AROUND
100-300 FEET SO EXPECTING DENSE FOG AT TIMES THROUGH 17Z....THEN
LIFTING.

&&

.MARINE...AS OF 9:41 PM PST THURSDAY...GENERALLY LIGHT NORTHWEST
WINDS ARE EXPECTED TO PREVAIL THROUGH FRIDAY AFTERNOON...BUT ARE
EXPECTED TO INCREASE THROUGH THE WEEKEND. A LARGE LONG PERIOD
NORTHWEST SWELL WILL CONTINUE TO MOVE THROUGH THE AREA OVERNIGHT
AND PERSIST INTO THE WEEKEND. THIS LARGE SWELL WILL RESULT IN VERY
LARGE BREAKING WAVES NEAR OFFSHORE REEFS.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...HIGH SURF ADVISORY...ALONG COAST TIL 8 PM SATURDAY
             SCA...ROUGH BAR ADVISORY FOR SF BAR

&&

$$

PUBLIC FORECAST: DYKEMA
AVIATION: R_WALBRUN
MARINE: R_WALBRUN


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