SAN FRANCISCO BAY AREA/CENTRAL CALIFORNIA COAST FORECAST DISCUSSION
NWS SAN FRANCISCO CA
AFDMTR 900 AM PDT SAT JUL 10 1999
SATELLITE IMAGERY THIS MORNING SHOWS A SOLID BLANKET OF MARINE ST
CLOUDS ALONG THE COAST EXTENDING WELL INTO THE COASTAL VALLEYS BUT
NOT THE ERN SECTIONS OF ALAMEDA OR CONTRA COSTA COUNTIES. THIS
COVERAGE IS NEARLY IDENTICAL TO YESTERDAY MORNING...AND 12 OAK
SOUNDING AS WELL AS 8AM FT ORD PROFILER ARE A CARBON COPY OF
YESTERDAY MORNING. BOTH SHOW TOPS OF LAYER IN THE 1200-1500 FOOT
RANGE AND ONE AIRCRAFT REPORT OVER SFO INDICATED TOPS OF LOW CLOUDS
AT 1400 FEET...JUST SLIGHTY HIGHER THAN SOME REPORTS YESYERDAY. THE
ONLY ADDED INGREDIENT TO THE MIX TODAY IS SOME SUBTROPICAL HIGH LEVEL
MOISTURE THAT HAS MOVED INTO THE CENTRAL COAST FROM THE SW MONSOON...
FROM AZ AND SRN CA. SOUNDING SHOWS MOISTURE IN THE 12K-20K LEVEL OF
THE ATMOSPHERE...SUGGESTING SOME MID/HIGH CLOUDS PASSING OVER THE
AREA TODAY. NEW MODELS...AS PREVIOUS KEEP ALL THE DYNAMICS WITHIN
THIS SUBTROPICAL FLOW E AND S OF OUR AREA. MAIN CONVECTIVE POTENTIAL
APPEARS TO BE CENTERED OVER SRN SIERRA THIS AFTERNOON WITH WATER
VAPOR IMAGERY AND MODELS INDICATING A VORTMAX NEAR DEATH VALLEY
EARLIER THIS MORNING MOVING NWD INTO THE SRN SIERRA NEAR MONO LAKE AT
THIS TIME. ANOTHER VORTMAX MAY BE HEADING INTO SRN CA FROM NRN BAJA
PEN. ONLY EXPECT MID/HIGH CLOUDS FOR THE CENTRAL COAST...NO
THUNDERSTORMS BUT PERHAPS A FEW SPRINKLES IN THE SRN COASTAL
MOUNTAINS OR DIABLOS. SEVERAL WEAK UPPER LEVEL TROFS MOVING THROUGH
THE GULF OF ALASKA INTO THE PACIFIC NW ARE HELPING TO SHUNT THIS
SUBTROPICAL CLOUDINESS TO OUR S AND E. OTHERWISE...FAIRLY STATIC
CONDITIONS SHOULD PREVAIL OVER THE NEXT FEW DAYS. HIGH PRESSURE
ALOFT...AROUND 594 DM...CONTINUES FOR THE NEXT SEVERAL DAYS BUT THERE
IS ENOUGH ONSHORE SURFACE GRADIENT EACH AFTERNOON FOR A MODERATE
SEABREEZE TO DEVELOP KEEPING DAYTIME TEMPERATURES FROM SOARING.
STILL...EXPECT MILD AT THE COAST AND FAIRLY HOT...NEAR 100...WELL
INLAND WITH ONLY SMALL VARIATIONS DAY TO DAY INTO MID PORTION OF NEXT
WEEK.
POPS ZERO. MACPHERSON
.SFO...TDA...SCA...PT ARENA TO PT PIEDRAS BLANCAS AND SFO BAY THIS
AFTERNOON.