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000
FXUS66 KMTR 101749
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1049 AM PDT MON MAR 10 2014

.SYNOPSIS...PARTLY CLOUDY THIS AFTERNOON AS HIGH PRESSURE BUILDS.
LOCALLY GUSTY NORTH WINDS WILL DEVELOP ACROSS THE HILLS BY TUESDAY
MORNING OTHERWISE DRY WEATHER WILL RETURN FOR THE REST OF THE
WEEK. DAYTIME TEMPERATURES WILL SLOWLY WARM STARTING TUESDAY WITH
MUCH ABOVE NORMAL READINGS BY THE WEEKEND.

&&

.DISCUSSION...AS OF 08:52 AM PDT MONDAY...A WEAK FRONTAL BOUNDARY
CONTINUES TO PUSH THROUGH THE REGION THIS MORNING WITH LIGHT RAIN
REPORTED OVER THE SAN FRANCISCO BAY AREA AND DOWN THROUGH THE
SANTA CLARA VALLEY. PRECIPITATION ALONG THE BOUNDARY DOES APPEAR
TO BE DIMINISHING BASED ON THE LATEST RADAR TRENDS...HOWEVER
DRIZZLE OR LIGHT RAIN WILL STILL BE POSSIBLE THROUGH THE MORNING
AS THE BOUNDARY PUSHES THROUGH THE CENTRAL COAST. OVERALL...DRYING
WILL TAKE PLACE ONCE THE FRONT PUSHES THROUGH WITH FEW/SCT CLOUDS
THROUGH THE AFTERNOON. ONLY SLIGHTLY COOLER TEMPERATURES ON TAP
FOR THIS AFTERNOON.

&&

.PREV DISCUSSION...AS OF 3:00 AM PDT MONDAY...KMUX RADAR HAS INDICATED
MINOR ECHOS TONIGHT ACROSS PARTS OF THE NORTH BAY, HOWEVER TO
THIS POINT VIRTUALLY NONE OF IT IS REACHING THE GROUND. IN FACT,
BODEGA BAY IS THE ONLY SPOT WITH MEASURABLE RAINFALL IN OUR CWA  --
JUST 0.02". LATEST SWEEPS DO SHOW AN INCREASE IN RETURNS OFF THE COAST,
SO STILL FEE FAIRLY CONFIDENT THAT AT LEAST THE NORTH BAY WILL END
UP SEEING RAINFALL INTO THE MORNING HOURS AS A COLD FRONT RACES
ACROSS OUR AREA.

BIGGER QUESTION IS WHETHER OR NOT THE RAIN WILL MAKE IT AS FAR
SOUTH AS SF BAY AND THE CITY OF SAN FRANCISCO OR IF THIS WILL END
UP BEING A NORTH BAY EVENT. LATEST NAM GUIDANCE HAS TRENDED A BIT
DRIER AND MORE TO THE NORTH, AND BASED ON THE LIMITED RETURNS SO
FAR THE MORNING FORECAST REFLECTS LESS RAINFALL FOR ALL AREAS WITH
MOSTLY DRY CONDITIONS NOW ANTICIPATED SOUTH OF SAN MATEO COUNTY.
NOT OUT OF THE QUESTION THAT THE CITY OR PARTS OF THE EAST BAY
COULD PICK UP A STRAY SHOWER TODAY, SO DECIDED TO LEAVE A CHANCE
OF RAIN FOR THAT AREA THROUGH THE MORNING HOURS. QPF WAS SCALED
BACK FOR ALL SPOTS, SO ONLY 1/3" AT THE MOST IS FORECAST FOR NORTH
BAY MOUNTAINS, WITH GENERALLY 1/10"-1/4" POSSIBLE FOR NORTH BAY
COMMUNITIES. FOR LOCATIONS TO THE SOUTH LESS THAN A FEW HUNDREDTHS
CAN BE EXPECTED. ONLY COMMUTING ISSUES WOULD LIKELY BE FOR ROADS
THROUGH THE NORTH BAY FOR THOSE WITH EARLY MORNING DRIVES.

JUST AS QUICKLY AS THE STORM ARRIVES, IT WILL EXIT OUR AREA AND
HEAD OFF TO THE EAST BY THIS EVENING. BEHIND IT A SURFACE RIDGE
OF HIGH PRESSURE WILL BUILD IN FROM THE NORTH HELPING TO BOOST
OFFSHORE WINDS. HIGHER ELEVATION SPOTS FOR THE NORTH AND EAST BAY
COULD EASILY SEE GUSTS IN THE 20-30 MPH WHICH WILL LEAD TO
ELEVATED FIRE WEATHER CONCERNS. THE WINDS WILL SLOWLY DISSIPATE ON
TUESDAY AS THE GRADIENT WEAKENS.

TEMPERATURES WILL SLOWLY INCREASE THROUGH THE WEEK TO THE FIRST
PART OF NEXT WEEK AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL
MOVE BACK TO OUR AREA WHILE 850 MB TEMPS JUMP BACK TO THE 16-18C
RANGE (WHICH WOULD PUT THEM IN THE 95-99TH PERCENTILE FOR MARCH).
THIS WILL LEAD TO VERY NICE CONDITIONS FOR NEXT WEEKEND --
POSSIBLY A FEW RECORDS COULD BE SET ON SUNDAY. CASE IN POINT IS
PINNACLES WHICH HAS A RECORD HIGH OF 91 FOR THE DATE. IF THE ECMWF
VERIFIES, WE WILL BE CLOSE TO THAT VALUE.

DRY WEATHER WILL HOLD THROUGH AT LEAST THE FIRST HALF OF NEXT
WEEK. THE RIDGE IS FORECAST TO START TO BREAK DOWN BY THE MIDDLE
OF NEXT WEEK WHICH COULD FINALLY ALLOW A SYSTEM TO WORK ITS WAY
INTO OUR AREA AS WE APPROACH THE LAST FULL WEEK OF MARCH.

&&

.AVIATION...AS OF 10:49 AM PDT MONDAY...FOR 18Z TAFS. FRONTAL
BOUNDARY IS NOW SOUTH OF MONTEREY. WINDS HAVE SWITCHED NW AT ALL
THE TERMINALS WITH DRY AIR FILTERING IN. EXPECT VFR SKIES THIS
AFTERNOON WITH CLEAR SKIES OVERNIGHT. SOME LOCALLY STRONG
NORTH/NORTHEAST WINDS WILL DEVELOP LATE TONIGHT INTO TUESDAY WITH
LOW LEVEL TURBULENCE AND SHEAR POSSIBLE BUT LITTLE IMPACT AT THE
TERMINALS.

VICINITY OF KSFO...VFR SKIES THIS AFTERNOON AND TONIGHT WITH GUSTY
NW WINDS DEVELOPING.

KSFO BRIDGE APPROACH...SAME AS SFO.

MONTEREY BAY AREA TERMINALS...SOME LOW CIGS THROUGH MIDDAY THEN
CLEARING SKIES AS DRY AIR FILTERS IN. EXPECTING VFR LATER THIS
AFTERNOON AND TONIGHT.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...PT ARENA TO PT REYES 0-10 NM
             SCA...PT REYES TO PIGEON PT 0-10 NM
             SCA...PIGEON PT TO PT PINOS 0-10 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             SCA...PIGEON PT TO PT PINOS 10-60 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
             SCA...PT ARENA TO PT REYES 10-60 NM
             SCA...PT REYES TO PIGEON PT 10-60 NM

&&

$$

PUBLIC FORECAST: RGASS
AVIATION: RWW

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