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

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000
FXUS66 KMTR 020047
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
547 PM PDT SAT AUG 1 2015

.SYNOPSIS...A SUBTLE COOLING TREND IS FORECAST TO CONTINUE INTO
EARLY NEXT WEEK AS ONSHORE FLOW AND THE MARINE INFLUENCE
INCREASES. ASIDE FROM PATCHY COASTAL DRIZZLE AND FOG DURING THE
OVERNIGHT AND EARLY MORNING HOURS...DRY WEATHER CONDITIONS WILL
LIKELY PERSIST THROUGH THE FORECAST PERIOD.

&&

.DISCUSSION...AS OF 02:40 PM PDT SATURDAY...GENERALLY CLEAR SKIES
PREVAIL ACROSS THE REGION THIS AFTERNOON AS LOW CLOUDS HAVE
DISSIPATED OVER JUST ABOUT ALL INLAND AREAS. HOWEVER...THE FORT
ORD PROFILER CONTINUES TO SHOW A MARINE LAYER AROUND 2000 FEET
DEEP AND SHOULD SUPPORT A RETURN OF STRATUS TONIGHT. MANY OF THE
HIGH RESOLUTION MODELS ARE SHOWING SIGNS OF PATCHY COASTAL DRIZZLE
AS WELL. THUS...HAVE ADDED PATCHY FOG AND DRIZZLE IN THE FORECAST
FOR TONIGHT INTO EARLY SUNDAY MORNING.

THE OVERALL PATTERN IS NOT FORECAST TO CHANGE MUCH IN THE NEXT 24
TO 48 HOURS WITH AN UPPER LEVEL RIDGE OF HIGH PRESSURE TO OUR EAST
AND A TROUGH OUT OVER THE EASTERN PACIFIC. INCREASED ONSHORE FLOW
AND PERSISTENT MARINE INFLUENCE WILL RESULT IN DAYTIME
TEMPERATURES ON THE COOL SIDE OF NORMAL THROUGH EARLY NEXT
WEEK...ESPECIALLY OVER INLAND AREAS. THIS PATTERN WILL ALSO
SUPPORT DRY WEATHER CONDITIONS THROUGH EARLY NEXT AS A SLIGHTLY
COOLER AND DRY AIR MASS REMAINS ALOFT.

TEMPERATURES ARE FORECAST TO REBOUND BACK TO NEAR SEASONAL
AVERAGES FOR THE MIDDLE OF NEXT WEEK IN RESPONSE TO BUILDING HIGH
PRESSURE OVER THE DESERT SOUTHWEST. THIS WARM-UP IS FORECAST TO BE
SOMEWHAT SHORT-LIVED AS THE GFS AND ECMWF BOTH SHOW A WEAK
MID/UPPER LEVEL LOW DEVELOPING OFF OF OUR COAST LATE NEXT WEEK. AS
THE SYSTEM APPROACHES...A SLIGHT COOLING TREND CAN BE EXPECTED
REGION-WIDE. WILL ALSO CONTINUE WITH A DRY FORECAST GIVEN LIMITED
MOISTURE ALOFT ASSOCIATED WITH THE APPROACHING UPPER LEVEL SYSTEM.

&&

.AVIATION...AS OF 5:34 PM PDT SATURDAY...VFR CONDITIONS PREVAIL
AREA-WIDE PER SATELLITE AND METAR OBSERVATIONS. THERE IS STILL A
FAIR AMOUNT OF HUMIDITY AROUND THE AREA NOT ONLY AT THE SURFACE
PER HIGHER DEWPOINTS BUT THE PRECIPITABLE WATER...TOTAL AMOUNT OF
WATER VAPOR IN THE ATMOSPHERIC COLUMN...ON THE EVENING 00Z OAKLAND
SOUNDING IS STILL ABOUT 1 INCH. GRADUAL LOWER LEVEL COOLING AS WELL
AS AN OVERALL INCREASE IN DRYING...AT LEAST IN THE MID TO UPPER
LEVELS...IS FORECAST SUNDAY INTO MONDAY. FOR THE TIME BEING THE
MARINE LAYER INVERSIONS WILL LIKELY REMAIN INTACT SUPPORTING STRATUS
AS WELL AS SOME FOG REDEVELOPMENT LATE TONIGHT AND SUNDAY MORNING.

VICINITY OF KSFO...HIGH CONFIDENCE VFR CONTINUES INTO THE EVENING
AND THERE MAY BE A FEW WESTERLY WIND GUSTS UP TO 20-22 KNOTS TIL
03Z. MVFR CIG 08Z-12Z FOLLOWED BY PREVAILING MVFR CIG TIL 17Z IS A
LOW TO MODERATE CONFIDENCE FORECAST.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...MODERATE TO HIGH CONFIDENCE VFR
HOLDS THROUGH MOST OF THE EVENING. IFR CIGS FORECAST WITH TEMPO
GROUPS 06Z-10Z. MID TO LATE MORNING CLEARING EXPECTED SUNDAY.

&&

.MARINE...AS OF 02:40 PM PDT SATURDAY...PREDOMINATELY LIGHT
NORTHWEST WINDS AND THROUGH THE WEEKEND. LIGHT MIXED SEAS WITH A
LONG PERIOD SOUTHERLY SWELL THROUGH THE FORECAST.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...NONE.

$$

PUBLIC FORECAST: RGASS
AVIATION: CANEPA
MARINE: DRP


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