FXUS66 KMTR 310352
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
852 PM PDT FRI JUL 30 2010

.DISCUSSION...AS OF 8:50 PM PDT FRIDAY...TEMPERATURES ACROSS OUR
REGION HAVE BEEN CONSISTENTLY BELOW NORMAL FOR THE SECOND HALF OF
JULY. TODAY WAS NO EXCEPTION AS MOST LOCATIONS POSTED HIGH
TEMPERATURES THAT WERE ANYWHERE FROM 5 TO 10 DEGREES BELOW NORMAL.
THE UPPER LEVEL TROUGH NEAR THE WEST COAST THAT HAS BEEN RESPONSIBLE
FOR OUR CURRENT COOL SPELL IS FORECAST TO LIFT TO THE NORTHEAST OVER
THE NEXT COUPLE OF DAYS. AS IT DOES SO...HEIGHTS WILL INCREASE...THE
AIRMASS WILL WARM ALOFT...AND THE MARINE LAYER SHOULD COMPRESS
SOMEWHAT. THIS WILL RESULT IN A GRADUAL WARMING TREND THROUGH THE
WEEKEND. BY SUNDAY...TEMPERATURES SHOULD BE CLOSE TO NORMAL...AT
LEAST INLAND. PERSISTENT MARINE LAYER CLOUDS AND ONSHORE FLOW WILL
MAINTAIN COOL CONDITIONS NEAR THE OCEAN. HOWEVER...AN INCREASING
NORTHERLY SURFACE GRADIENT MAY RESULT IN SOME COASTAL CLEARING THIS
WEEKEND...BUT MAINLY NORTH OF SAN FRANCISCO.

NOT MUCH CHANGE IS EXPECTED NEXT WEEK. BOTH THE GFS AND ECMWF
MAINTAIN WEAK UPPER LEVEL TROUGHINESS NEAR THE WEST COAST FOR
MOST OF THE WEEK...ALONG WITH LIGHT TO MODERATE ONSHORE FLOW.
TEMPERATURES WILL CONTINUE SLIGHTLY BELOW NORMAL THROUGH ABOUT
THURSDAY. WEAK RIDGING LATE IN THE WEEK MAY PUSH TEMPERATURES UP TO
NORMAL BY FRIDAY...OR PERHAPS EVEN A BIT ABOVE NORMAL.

&&

.AVIATION...AS OF 4:50 PM PDT FRIDAY...ONSHORE GRADIENTS ARE A BIT
STRONGER THIS AFTERNOON COMPARED TO YESTERDAY AFTERNOON. THUS...WOULD
EXPECT LOW CIGS TO DEVELOP INLAND EARLIER THAN LAST EVENING.
HOWEVER...THE FORT ORD PROFILER INDICATES THE HEIGHT OF THE MARINE
VERSION IS A LITTLE LOWER. THUS...BELIEVE TIMING FOR INLAND
DEVELOPMENT OF IFR CIGS THIS EVENING WILL BE SIMILAR TO LAST
EVENING. INLAND CLEARING WILL OCCUR AROUND 18Z ON SATURDAY.

VICINITY OF KSFO...IFR CIGS DEVELOPING AROUND 03-04Z...CLEARING
AROUND 17-18Z ON SATURDAY. WEST WINDS FOR THE LATE AFTERNOON
AND EVENING HOURS WITH GUSTS AS HIGH AS 25 KNOTS.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO EXCEPT CIGS DEVELOPING ABOUT
AN HOUR LATER THIS EVENING.

MRY BAY AREA TERMINALS...IFR CONDITIONS AND NORTHWEST ONSHORE FLOW
WILL KEEP IFR CIGS IN THROUGH MIDDAY SATURDAY. LOCAL MVFR VSBYS
EXPECTED LATE TONIGHT AND EARLY ON SATURDAY.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PIGEON PT 10-60 NM.
                ...PT ARENA TO PT REYES 0-10 NM.
                ...SFO BAY TIL 11 PM.

&&

$$

PUBLIC FORECAST: DYKEMA
AVIATION/MARINE: DYKEMA

NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO