FXUS66 KMTR 150600
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
1000 PM PST MON DEC 14 2009

.DISCUSSION...AS OF 8:45 PM PST MONDAY...INCREASING CLOUD COVER
ANTICIPATED TONIGHT AS AN APPROACHING WEATHER SYSTEM NEARS THE
NORTH COAST. ALTHOUGH THE BULK OF THE PRECIPITATION IS EXPECTED TO
STAY NORTH OF THE SONOMA/MENDOCINO COUNTY LINE A FEW SHOWERS WILL
CROSS OVER THE BORDER INTO OUR AREA OF RESPONSIBILITY. LATEST RADAR
IMAGERY SHOWS SCATTERED RADAR RETURNS OFF THE COAST HEADED TOWARD
THE NORTHERNMOST PORTION OF THE CWA. RAIN IS ANTICIPATED TO
GRADUALLY SPREAD SOUTH OVERNIGHT REACHING THE BAY AREA TUESDAY
EVENING.

AMSU TPW IMAGERY CONTINUES TO DEPICT HIGH PRECIPITABLE WATER VALUES
IN EXCESS OF ONE INCH THAT ARE POISED TO MOVE ONSHORE OVER THE
NORTHERN CALIFORNIA COAST TONIGHT. AS MENTIONED BEFORE...THE NORTH
BAY REGION WILL SEE RAIN SPREAD SOUTHWARD OVERNIGHT. RAIN WILL REACH
THE BAY AREA TUESDAY EVENING AND CONTINUE THROUGH WEDNESDAY. FORECAST
RAINFALL TOTALS OF UP TO 3 INCHES ARE EXPECTED OVER THE HILLS OF THE
NORTH BAY WITH ANYWHERE FROM AN INCH TO AND INCH AND A HALF IN THE
NORTH BAY VALLEYS. THE BAY AREA WILL MEASURE ANYWHERE FROM A QUARTER
TO HALF INCH WITH THE SANTA CRUZ MOUNTAINS CATCHING ABOUT A HALF AN
INCH. THE MONTEREY BAY REGION WILL LIKELY ONLY SEE A TENTH OF AN INCH
AS THE SYSTEM PETERS OUT OVER THE REGION LATE WEDNESDAY AFTERNOON AND
EVENING.

DRIER WEATHER IS ON TAP THURSDAY AS WE TRANSITION BETWEEN STORMS. A
WEAK FLAT RIDGE WILL KEEP THE WEATHER DRY AND MILD THURSDAY AND
FRIDAY. MODELS SOLUTIONS DIFFER AT THIS POINT WITH THE GFS
CONTINUING TO MOVE A DISTURBANCE ACROSS NORTHERN CALIFORNIA WHILE
THE ECMWF MAINTAINS THE RIDGE IN PLACE AND KEEPS THE STORM TRACK
FARTHER NORTH. HAVE MAINTAINED THE CURRENT FORECAST THINKING FOR
NOW AND KEPT THE DISTRICT DRY THROUGH THE WEEKEND PER ECMWF
GUIDANCE.

FORECAST REMAINS ON TRACK...NO UPDATES NEEDED AT THIS TIME.

&&

.AVIATION...AS OF 10:00 PM PST MONDAY...VFR CONTINUES AT AREA
AIRPORTS TONIGHT. CLOUDS WILL GRADUALLY MOVE IN FROM THE WEST
OVERNIGHT.

VICINITY OF KSFO...VFR AND LIGHT WINDS. LIGHT RAIN POSSIBLE LATE IN
THE DAY TUESDAY.

KSFO BRIDGE APPROACH...VFR.

MRY BAY AREA TERMINALS...VFR. LIGHT WINDS.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PIGEON PT 10 TO 60 NM OFFSHORE
                ...PT ARENA TO PT REYES TO 10 NM
$$

PUBLIC FORECAST: CW
AVIATION/MARINE: CANEPA

NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO