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000
FXUS66 KMTR 071131
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
331 AM PST FRI MAR 7 2014

.SYNOPSIS...HIGH PRESSURE WILL BRING MOSTLY SUNNY AND SEASONABLY
MILD TEMPERATURES TO THE BAY AREA TODAY THROUGH SATURDAY. THE NEXT
WARM FRONT WILL MOVE INTO THE NORTH BAY SUNDAY WITH A CHANCE OF
LIGHT RAIN. RAIN CHANCES WILL SPREAD SOUTHWARD INTO THE GREATER
BAY AREA ON MONDAY. ANY SHOWERS WILL END BY MONDAY EVENING AS HIGH
PRESSURE BEGINS TO BUILD. MILD AND DRY TUESDAY THROUGH FRIDAY.

&&

.DISCUSSION...AS OF 3:28 AM PST FRIDAY...MAIN FORECAST FOCUS WILL
DEAL WITH RAIN CHANCES SUNDAY INTO MONDAY. IN THE MEANTIME PLEASANT
EARLY SPRING WEATHER ON TAP TODAY AND SATURDAY.

.SHORT TERM...SOME HIGH CLOUDS ARE BEGINNING TO SPILL OVER THE
NORTH BAY WITH FOG PRODUCT SHOWING PATCHY FOG ALONG THE SAN MATEO
COAST...DOWN THE SANTA CLARA VALLEY AND AROUND MONTEREY BAY. MODEL
CROSS SECTIONS SHOWING PLENTY OF SUNSHINE FROM MID MORNING AND
THROUGH THE AFTERNOON HOURS WITH TEMPERATURES FROM THE UPPER 60S
TO LOWER 70S MOST LOCATIONS.

NOT MUCH CHANGE IN THE WEATHER OVERNIGHT INTO SATURDAY WITH
ANOTHER ROUND OF PATCHY VALLEY FOG AND RELATIVELY MILD OVERNIGHT
LOWS IN THE 40S. THE WEATHER ON SATURDAY LOOKS IDEAL TO START OUT
THE WEEKEND WITH PLENTY OF SUNSHINE AND COMFORTABLE TEMPERATURES
FROM THE UPPER 60S TO UPPER 70S.

MAIN FORECAST CHALLENGE STARTS AS EARLY AS SATURDAY EVENING AS A
WARM FRONT WILL SLOWLY APPROACH THE NORTH BAY. USUALLY SLOW IS THE
WAY TO GO WITH WARM FRONTAL RAINS SO RAIN CHANCES IN THE NORTH BAY
MAY BE OVERSTATED SATURDAY EVENING WITH NO RAIN CONCERNS SOUTH OF
THE GOLDEN GATE FOR SATURDAY NIGHT.

MODEL CONSENSUS BRINGS LIGHT RAIN INTO THE NORTH BAY ON SUNDAY
WITH HEAVY RAIN FOCUSED JUST TO OUR NORTH OVER MENDOCINO COUNTY.
DRY AND MILD WEATHER FOR THE REST OF THE DISTRICT UNDER MILD
SOUTHERLY FLOW. THE WARM FRONT WILL HANG OVER THE NORTH BAY RIGHT
THROUGH SUNDAY NIGHT. THEN A SHORTWAVE TROUGH WILL FINALLY KICK
THE BOUNDARY SOUTHWARD INTO THE GREATER BAY AREA BY MONDAY MORNING
WITH A ROUND OF MAINLY LIGHT RAIN EXPECTED TO PASS THROUGH THE
GREATER BAY AREA WITH LITTLE OR NO RAIN FOR THE MONTEREY BAY
REGION. STORM TOTALS OVER THE FAR NORTH BAY COULD BE 0.50-1.00
WITH 0.10-0.25 POSSIBLE FOR THE GREATER BAY AREA BY MONDAY
AFTERNOON. SIMILAR TO THE LAST EVENT MUCH LIGHTER RAIN AMOUNTS FOR
THE SOUTH BAY AND MONTEREY BAY REGION AS THE STRONG COLD ADVECTION WILL
NEVER REALLY GET SOUTH OF INTERSTATE 80.

AFTER THE MONDAY TROUGH PASSES THROUGH STRONG HIGH PRESSURE WILL
BUILD FOR MUCH OF NEXT WEEK. EXPECT MOSTLY CLEAR SKIES WITH
TEMPERATURES TRENDING ABOVE NORMAL...PLENTY OF READINGS IN THE 70S
AND PROBABLY EVEN SOME 80S IF OFFSHORE FLOW AND THE STRENGTHENING
MARCH SUN ANGLE COME TOGETHER. BOTH THE GEM AND ECMWF BUILD A VERY
STRONG RIDGE (593 DM ON THE GEM) BY THE WEEKEND OF THE 15/16TH
WHICH WOULD IMPLY VERY WARM TEMPS AS 850 MB TEMPS APPROACH 15 CELSIUS.

THERE IS REASONABLY GOOD EVIDENCE THAT THE RIDGE WILL BREAK DOWN
WITH HOPE FOR MORE MUCH NEEDED RAINFALL TOWARDS THE SECOND HALF OF
THE MONTH.

&&

.AVIATION...AS OF 3:29 AM PST FRIDAY...TRICKY FORECAST THIS MORNING
WITH BROKEN STRATUS AS HIGH CLOUDS CONT TO STREAM IN FROM THE NW.
DENSE FOG STILL SEEM POSS AT KSTS DESPITE THE HIGH CLOUDS...BUT
ELSEWHERE NOT AS MUCH. SAN FRANCISCO BAY HAS HAD SOME PATCHY HAZE/FOG
TO NEAR 6-7 MILES AND THAT WILL REMAIN THROUGH THIS MORNING.
OTHERWISE...WILL HAVE SOME PATCHY CIGS POSS THIS MORNING THEN MAINLY
VFR TODAY WITH MORE MID-HIGH LEVEL CLOUDS.  FOR TONIGHT...IT APPEARS
THAT OFFSHORE FLOW WILL GRADUALLY DEVELOP AS HIGH PRESSURE BUILDS
INLAND. OVERALL CONF IS MEDIUM


VICINITY OF KSFO...FOR KSFO...PATCHY CIGS ARE WAITING IN THE
WINGS...OR AT LEAST IT APPEARS THAT WAY ON THE CAMS AND SATELLITE.
NOT TOTALLY SURE IF THEY WILL MOVE OVER THE AIRPORT...BUT GIVEN THE
NW WINDS WILL ALLOW FOR A FEW HOURS OF CIGS THIS MORNING VIA A
TEMPO GROUP. KOAK A FEW-SCT CLOUDS POSS THIS MORNING. VFR THIS
AFTERNOON WITH BREEZY ONSHORE FLOW.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...CIGS ARE VERY CLOSE TO THE RUNWAY AT
MRY...BUT NOT OVER THE AIRPORT YET. WILL FORECAST FOR SOME PATCHY
CIGS TO MOVE OVER THE AIRPORT CLOSE TO SUNRISE. KSNS WILL LIKELY
STAY VFR.  VFR FOR MONTEREY BAY AREA THIS AFTERNOON.

&&

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

&&

$$

PUBLIC FORECAST: RWW
AVIATION: MM

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