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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1125 AM PDT SAT APR 25 2015

.SYNOPSIS...HIGH PRESSURE WILL PRODUCE WARM AND DRY CONDITIONS ON
SUNDAY AND MONDAY. A COOLING TREND WILL DEVELOP BY THE MIDDLE OF
NEXT WEEK AS A DRY UPPER TROUGH DEVELOPS OVER NORTHERN CALIFORNIA.

&&

.DISCUSSION...AS OF 09:00 AM PDT SATURDAY... THE COLD FRONT AND
ASSOCIATED PRECIPITATION BAND HAS NEARLY MOVED OUT OF THE FORECAST
AREA ALREADY THIS MORNING. THE FRONT IS CURRENTLY OVER SOUTHERN
MONTEREY AND SAN BENITO COUNTIES. A FEW ISOLATED SHOWERS MAY
DEVELOP IN THE POST FRONTAL ENVIRONMENT HOWEVER MOST LOCATIONS ARE
FINISHED RECEIVING RAIN FROM THIS STORM. PRELIMINARY RAINFALL
TOTALS ARE IMPRESSIVE CONSIDERING THE SPEED AT WHICH THIS SYSTEM
SWEPT THROUGH THE AREA. THE BIG SUR MOUNTAINS PICKED UP THE MOST
PRECIPITATION WITH MANY PEAKS REPORTING OVER TWO INCHES WITH PICO
BLANCO PICKING UP 2.52 INCHES. RAINFALL TOTALS BETWEEN A QUARTER
AND THREE QUARTERS OF AN INCH HAVE BEEN OBSERVED THROUGHOUT MANY
LOW LYING URBAN AREAS. DOWNTOWN SAN FRANCISCO FALLS IN THE MIDDLE
OF THESE VALUES WITH .47 OF AN INCH. SEE THE LATEST PNSMTR FOR
ADDITIONAL CITY BY CITY RAINFALL TOTAL OBSERVATIONS. I HAVE
ALREADY UPDATED THE FORECAST PACKAGE TO ADJUST RAIN
PROBABILITIES... SKY COVER... AND WEATHER FOR THIS MORNING SO THE
LATEST ZFPMTR SHOULD BE GOOD TO GO. FOR THE REST OF THE DAY...
EXPECT PARTLY CLOUDY SKIES WITH BREEZY CONDITIONS BY THE
AFTERNOON.

HIGH PRESSURE BUILDS INTO THE REGION BY TOMORROW LEADING TO A
GENERAL WARMING AND DRYING TREND. MONDAY WILL BE THE WARMEST DAY
OF THE NEXT SEVERAL WITH HIGHS RANGING FROM THE 60S ALONG COAST TO
80S INLAND.


&&

.AVIATION...AS OF 11:25 AM PDT SATURDAY...FOR 18Z TAFS. REGION IS
IN POST FRONTAL REGIME WITH GUSTY NW ONSHORE WINDS ALLOWING SOME
CLOUDS TO PILE UP ALONG THE COASTAL HILLS. IN GENERAL EXPECT
CLOUDS TO BECOME SCATTERED THROUGH THE AFTERNOON EXCEPT NEAR
MONTEREY BAY WHERE BKN CIGS MAY PREVAIL. OTHER ISSUE WILL BE
STRONG WESTERLY WINDS WITH GUSTS TO 30 KT ALREADY AT KSFO. WINDS
WILL GRADUALLY EASE THIS EVENING AND ENOUGH BOUNDARY LAYER
MOISTURE FOR LOW CLOUDS TO REFORM. EXPECT MORE RAPID CLEARING
SUNDAY MORNING.

VICINITY OF KSFO...LATEST OBS AND WEB-CAMS NOW SHOWING SCT CLOUDS.
EXPECT THIS TO PREVAIL THROUGH THE DAY. WEST WINDS ALREADY GUSTING
TO 30 KT AND EXPECT THIS TO CONTINUE AT LEAST THROUGH SUNSET.

CONFIDENCE IS MODERATE TO HIGH. 

SFO BRIDGE APPROACH...SIMILAR TO KSFO. BUT WINDS NOT QUITE AS
STRONG.
 
MONTEREY BAY AREA TERMINALS..NW ONSHORE WINDS ALLOWING LOW CLOUDS
TO PILE UP ON MONTEREY PENINSULA THIS AFTERNOON. CURRENT OVC006 AT
KMRY SHOULD LIFT ABOVE 1000 FEET BUT CIGS MAY PREVAIL AT KMRY AND
KSNS THROUGH THE DAY. HAVE PUT A TEMPO SCT GROUP FOR THIS AFTERNOON.
EXPECT LOW CIGS TO REFORM OVERNIGHT.

CONFIDENCE IS MODERATE. 

&&

.MARINE...AS OF 11:25 AM PDT SATURDAY...GUSTY NW WINDS WILL
CONTINUE TODAY THROUGH SUNDAY BEHIND LAST NIGHTS COLD FRONTAL
PASSAGE. MODERATE NORTHERLY WINDS ARE FORECAST TO PREVAIL THROUGH
MIDWEEK AS HIGH PRESSURE BUILDS OVER THE EASTERN PACIFIC AND THE
SURFACE PRESSURE GRADIENT STRENGTHENS. THE STRENGTHENING WINDS
WILL RESULT IN DETERIORATING SEA CONDITIONS.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...PT ARENA TO PT REYES 10-60 NM FROM 5 PM
             SCA...PT REYES TO PIGEON PT 10-60 NM FROM 5 PM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 7 PM
             SCA...PIGEON PT TO PT PINOS 10-60 NM FROM 7 PM
             SCA...PT ARENA TO PT REYES 0-10 NM FROM 5 PM
             SCA...PT REYES TO PIGEON PT 0-10 NM FROM 2 PM
             SCA...SF BAY NORTH OF THE BAY BRIDGE FROM 2 PM
             SCA...SF BAY SOUTH OF THE BAY BRIDGE FROM 2 PM

&&

$$

PUBLIC FORECAST: DRP
AVIATION/MARINE: RWW

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