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

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000
FXUS66 KMTR 081105
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
305 AM PST MON FEB 8 2016

.DISCUSSION...

.SYNOPSIS...A STRONG RIDGE OF HIGH PRESSURE WILL REMAIN POSITIONED
OVER THE WEST COAST MONDAY RESULTING IN THE POTENTIAL FOR RECORD
WARMTH ACROSS THE BAY AREA AND CENTRAL COAST TODAY. THE RIDGE
WILL BEGIN TO WEAKEN TOMORROW...INITIATING A COOLING TREND WHICH
WILL BRING TEMPERATURES BACK TO SEASONAL NORMS THROUGH VALENTINES
DAY WEEKEND. OUTSIDE OF A SLIGHT CHANCE FOR RAIN OVER THE NORTH
BAY FRIDAY AND FRIDAY NIGHT, DRY WEATHER IS FORECAST.

&&

.DISCUSSION...AS OF 3:00 AM PST MONDAY...CLEAR SKIES ACROSS THE
BOARD THIS MORNING AS A MODERATE TO STRONG OFFSHORE FLOW REMAINS
IN CHARGE. CURRENT SURFACE ANALYSIS INDICATES A GREATER THAN 15 MB
DIFFERENCE FROM SFO TO WMC WITH NEARLY 2 MB OFFSHORE FROM SFO TO
SAC. BIGGER PICTURE SHOWS AN UNUSUALLY ROBUST RIDGE OF HIGH
PRESSURE OVERHEAD (586 DM AT 500 MB) COMBINED WITH 16C AT 850 MB.
ALL OF THESE FACTORS WILL COMBINE TO CREATE ANOTHER ROUND OF
RECORD TO NEAR RECORD HIGHS ACROSS OUR ENTIRE REGION. MANY URBAN
SPOTS WILL BE IN THE UPPER 60S TO MID 70S WITH A FEW LOCATIONS IN
THE UPPER 70S TO LOWER 80S.

THE RIDGE AXIS WILL SHIFT OFF TO THE EAST STARTING ON TUESDAY
WHICH WILL HELP TO GRADUALLY BRING TEMPERATURES DOWN CLOSER TO
NORMAL VALUES. AT THE SAME TIME A LONGWAVE TROF WILL APPROACH THE
COAST AND BY FRIDAY RAIN WILL MOVE FROM NORCAL UP TO BC. FOR OUR
REGION, MODELS SHOW AN OUTSIDE CHANCE OF LIGHT RAIN HITTING THE
NORTH BAY SO LEFT A MENTION OF THAT IN THE FORECAST.

BEHIND THE TROF THE FLOW WILL ALTERNATE BETWEEN ZONAL AND A FLAT
RIDGE AT LEAST INTO NEXT TUESDAY. AFTER THAT, SOME INDICATION
THAT MOISTURE COULD BECOME ENTRAINED IN THE FLOW AND BRING RAIN
BACK TO OUR REGION DURING THE MIDDLE TO END OF NEXT WEEK.

BOTTOM LINE...NO PUBLIC ZONE HAZARDS EXPECTED THROUGH THE NEXT 7
DAYS.

&&

.AVIATION...AS OF 3:45 PM PST SUNDAY...VFR CONDITIONS PREVAIL
WITH CLEAR SKIES.

NORTHEAST WINDS AROUND 25 TO 30 KT WILL CONTINUE AT THE 1000-2000
FEET MSL LEVEL INTO EARLY EVENING WITH RESULTING LLWS CONCERNS FOR
MAINLY ACROSS KOAK AND KSFO AND POINTS NORTHWARD. THESE STRONGER
WINDS ABOVE THE SURFACE ARE FORECAST TO TAPER OFF BY AROUND 04Z
TONIGHT AND THE THREAT OF LLWS WILL DECREASE OVERNIGHT. LOCALLY
BREEZY AND GUSTY WINDS HAVE ALSO BEEN OBSERVED IN PORTIONS OF THE
BAY AREA...NEAR THE EAST BAY HILLS AND ALSO IN THE SOUTH BAY FROM
KSJC TO MILPITAS TO KPAO. MOST OF THESE LOCALLY BREEZY CONDITIONS
WILL DECREASE AS THE SUNSETS.

FOR MONDAY...OFFSHORE FLOW IS EXPECTED TO CONTINUE BUT MODELS SHOW
EASTERLIES BLO 10 KTS. GENERALLY CLEAR SKIES EXPECTED TO
CONTINUE.

VICINITY OF KSFO...VFR WILL PREVAIL. LIGHT NE FLOW AT THE SFC
WITH MODERATE LLWS EXPECTED INTO THE EARLY EVENING. COULD SEE A
FEW GUSTS TO AROUND 15 KT DURING THE LATE AFTERNOON BUT
CONFIDENCE IS LOW WHETHER WINDS WILL MIX DOWN.

SFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...LIGHT WINDS. VFR.

&&

.BEACHES...AS OF 10:45 PM PST FRIDAY...SWELLS OFF THE COAST HAVE
DECREASED TO 7 TO 8 FEET TONIGHT BUT THE SWELL PERIODS CONTINUE AT
14 TO 15 SECONDS. ALTHOUGH THE WAVES ARE LOWER THE LONGER PERIODS
MAKE THE WAVES CAPABLE OF GENERATING STRONG RIP CURRENTS AND LARGE
SHORE BREAK. ADDITIONALLY...WATER TEMPERATURE IS ONLY EXPECTED TO
BE IN THE MID 50S...SO THOSE VENTURING INTO THE WATER WILL ALSO BE
SUBJECT TO A HEIGHTENED RISK OF HYPOTHERMIA.

&&

.CLIMATE...RECORD HIGHS FOR MONDAY...

CITY NAME       FEB 8TH HIGH AND YEAR
--------------------------------------
KENTFIELD        71 IN 2006
SAN RAFAEL       72 IN 1980
NAPA             73 IN 1987
SAN FRANCISCO    74 IN 2006
SFO AIRPORT      73 IN 2006
OAKLAND MUSEUM   77 IN 2006
OAKLAND AIRPORT  70 IN 2006
RICHMOND         78 IN 2011
LIVERMORE        78 IN 1917
SAN JOSE         75 IN 1987
GILROY           78 IN 1963

MONTEREY         81 IN 1954
SANTA CRUZ       78 IN 1954
SALINAS          83 IN 2006
SALINAS AIRPORT  83 IN 1954
KING CITY        84 IN 2006

&&

.MARINE...AS OF 8:30 PM PST SUNDAY...A LARGE RIDGE OF HIGH
PRESSURE OVER THE WESTERN STATES WILL KEEP LIGHT WINDS ACROSS THE
COASTAL WATERS TODAY. OFFSHORE WINDS ARE FORECAST TO DEVELOP
MONDAY AND TUESDAY AS THE SURFACE THERMAL TROUGH DRIFTS OFF THE
COAST. AN ONSHORE FLOW WILL FINALLY DEVELOP BY MIDWEEK AS THE HIGH
WEAKENS. A LONG PERIOD SWELL WILL IMPACT THE COAST MONDAY.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...NONE.

$$

PUBLIC FORECAST: BELL
AVIATION: BRENCHLEY
MARINE: SIMS
CLIMATE: R_WALBRUN


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