000
FXUS66 KMTR 230125
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
525 PM PST WED FEB 22 2012

.DISCUSSION...AS OF 3:00 PM PST WEDNESDAY...TEMPERATURES HAVE
WARMED NICELY ACROSS THE CWA AND IT LOOKS LIKE A FEW RECORDS WILL
EITHER BE SET OR ARE WILL BE IN JEOPARDY. A FEW SPOTS AROUND THE
BAY HAVE HIT THE MID TO UPPER 70S AND WOULD SUSPECT THAT AT LEAST
A COUPLE OF THOSE WILL REACH 80. SHOULD DEFINITELY SEE SOME PERSONAL
WEATHER STATIONS WITH UNOFFICIAL READINGS WILL HITTING THAT RANGE.

THE WARM WEATHER IS THANKS TO A COMBINATION OF HIGH PRESSURE AND
FAVORABLE FLOW AT THE SURFACE. SFO-ACV HAS RAMPED UP TO OVER 8 MB
AND WITH SFO-SAC AT OR EVEN LESS THAN 1 MB...WOULD EXPECT CLEAR
CONDITIONS TONIGHT. WINDS SHOULD STAY UP OVERNIGHT IN MANY AREAS
HELPING TO KEEP TEMPERATURES UP.

SPEEDS WILL CONTINUE TO INCREASE THROUGH THE DAY TOMORROW AND AS
925 MB AMOUNTS EXCEED 40 KTS GUSTS OVER 40 MPH ARE FORECAST TO
BECOME LIKELY OVER THE NORTH AND EAST BAY HILLS. WILL KEEP THE
ADVISORY GOING FOR THOSE SPOTS THROUGH THE DAY WITH SOME LOCAL
SPOTS (ESPECIALLY NORTH FACING SLOPES) NEARING 55 MPH. GUIDANCE
DOES DROP OFF THE SPEED BY EARLY THURSDAY AFTERNOON...HOWEVER
EXPERIENCE HAS SHOWN THAT IT USUALLY DOES THAT TOO QUICKLY.
THEREFORE FOR NOW WILL KEEP THE ADVISORY IN PLACE UNTIL 6 PM.
TEMPERATURES SHOULD BE ABOVE TO WELL ABOVE NORMAL WITH 70S
EXPECTED IN MANY LOCATIONS. WHETHER OR NOT TOMORROW WILL BE WARMER
IS A TOUGH CALL WITH THE VARIES MODEL GUIDANCE SHOWING HIGHS CLOSE
TO TODAY`S VALUES. 500 MB HEIGHTS ARE EXPECTED TO BE A BIT
LESS...SO TODAY WILL PROBABLY END UP BEING THE WARMEST DAY OF THE
WEEK BY A DEGREE OR TWO. HIGHS ON FRIDAY WILL BE 2 TO 6 DEGREES
COOLER IN MOST SPOTS AS AN ONSHORE FLOW KICKS BACK IN BY
AFTERNOON. WILL NEED TO KEEP AN EYE ON THIS AS AN ADJUSTMENT ON
THE EXPECTED START TIME OF THE CHANGE FOR THE FLOW WILL PRODUCE
ERRORS IN THE HIGHS.

MUCH COOLER WEATHER RETURNS BY THE WEEKEND AS THE FLOW REMAINS
ONSHORE WHILE 500 MB HEIGHTS DROP AS A STORM SYSTEM MOVES INTO THE
PACNW. PREVIOUS GUIDANCE EVEN HAD SOME MOISTURE ASSOCIATED WITH
THIS HITTING THE NORTH BAY. THAT IS LOOKING LESS AND LESS LIKELY
WHICH MEANS THE ONLY IMPACT WILL JUST BE CLOUDS WITH HIGHS IN THE
50S TO LOWER 60S. A FEW ENSEMBLE MEMBERS DUE BRING A FEW SPRINKLES
TO THE NORTH BAY...SO WILL KEEP THAT GOING IN THE FORECAST FOR NOW.

IN THE EXTENDED...STILL NO SIGN OF A MAJOR STORM IMPACTING OUR
AREA. ECMWF DOES HAVE THE SOUTHERN EXTENT OF MOISTURE FROM A PACNW
SYSTEM GOING ACROSS THE NORTHERN HALF OF THE CWA ON WEDNESDAY. GFS
KEEPS MUCH MORE OF THE ACTIVITY TO THE NORTH WITH JUST A GLANCING
BLOW HERE. AFTER THAT THE REST OF THE NEXT WEEK LOOKS QUIET.

FOR THOSE WANTING ACTIVE WEATHER THERE MAY BE SOME RELIEF IN THE
VERY FAR EXTENDED AS THE MJO TRANSITIONS FROM PHASE 2 TO 3 WHILE
MORE OF THE ENSEMBLES (PLUS THE ENSEMBLE MEAN) BRINGS THE MAIN
STORM TRACK CLOSER TO SF/MONTEREY BAY. EVEN THE 8-14 DAY OUTLOOK
NOW HAS NORMAL RAINFALL FOR THE CWA WITH ABOVE NORMAL JUST TO OUR
NORTH. FAR TOO EARLY TO GET EXCITED ABOUT RAINFALL POTENTIAL WAY
OUT IN THE SECOND WEEK OF MARCH...BUT IT IS WORTH KEEPING AN EYE
ON.

&&

AVIATION...AS OF 5:25 PM PST WEDNESDAY...VFR CONDITIONS WILL
PERSIST THROUGH THE FORECAST PERIOD AS HIGH PRESSURE OVER THE
REGION MAINTAINS NORTHERLY FLOW OVER THE DISTRICT. GUSTY WINDS
WILL PERSIST THROUGH THIS EVENING THEN GRADUALLY DIMINISH
OVERNIGHT.

VICINITY OF KSFO...VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. GUSTY WEST WINDS TO AROUND 30 KT THROUGH THIS EVENING THEN
WINDS EXPECTED TO GRADUALLY TAPER OVERNIGHT.

KSFO BRIDGE APPROACH....SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...VFR CONDITIONS AND LIGHT WINDS
EXPECTED THROUGH THE FORECAST PERIOD.

&&

.CLIMATE...RECORD HIGH DATA FOR WEDS AND THURSDAY FOR REFERENCE

LOCATION      FEB 22ND RECORD   FEB 23RD RECORD
-------------------------------------------------
SANTA ROSA      77/1985          78/1985
SAN RAFAEL      79/1985          77/1985
NAPA            79/1985          80/1985
SF CITY         80/1985          80/1985
SFO             73/2002          73/1985
OAKLAND AIRPORT 78/1985          74/1985
LIVERMORE       76/2002          76/1915
MOFFETT FIELD   77/1985          76/1985
SAN JOSE        79/2002          76/2002
MONTEREY        77/1981          82/1954
SANTA CRUZ      78/1990          89/1896
SALINAS         80/1989          77/1990
KING CITY       88/1923          80/1980

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...WIND ADVISORY...NORTH AND EAST BAY HILLS STARTING AT 4 AM
             SCA...PT ARENA TO PT REYES 0-10 NM
             SCA...PT REYES TO PIGEON PT 0-10 NM
             SCA...PIGEON PT TO PT PINOS 0-10 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             GLW...PT ARENA TO PIGEON PT 10-60 NM
             SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 1 AM
             GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 1 AM

&&

$$

PUBLIC FORECAST: BELL
AVIATION/MARINE: CW
CLIMATE: RWW

NWS MTR Office Area Forecast Discussion