Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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000
FXUS66 KMTR 260556
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1056 PM 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 8:45 PM PDT SATURDAY...THE COLD FRONT THAT
BROUGHT WELCOME RAINFALL TO OUR REGION LAST NIGHT AND THIS MORNING
HAD QUICKLY ADVANCED INTO FAR SOUTHEAST CALIFORNIA BY LATE
AFTERNOON. PARTLY CLOUDY SKIES DEVELOPED BEHIND THE FRONT BY
AFTERNOON...BUT HIGH TEMPERATURES WERE BELOW NORMAL IN MOST AREAS
AS A COOL AIRMASS SWEPT IN FROM THE NORTHWEST. INCREASING POST-
FRONTAL NORTHWEST WINDS RESULTED IN BLUSTERY CONDITIONS NEAR THE
COAST AND IN THE HILLS. SAN FRANCISCO INTERNATIONAL AIRPORT
REPORTED A PEAK WIND GUST OF 45 MPH JUST PRIOR TO 6 PM THIS
EVENING AND WINDS ARE STILL GUSTING LOCALLY AS HIGH AS 45 MPH IN
THE COASTAL HILLS AT THIS HOUR. WINDS WILL GRADUALLY DECREASE
OVERNIGHT AS A SURFACE LOW CURRENTLY CENTERED NEAR LAS VEGAS
WEAKENS AND MOVES EAST.

THE COOL AIRMASS NOW IN PLACE...AND MOSTLY CLEAR SKIES WILL MEAN
A CHILLY NIGHT ACROSS OUR AREA. OVERNIGHT LOWS WILL DIP INTO THE
40S IN MOST LOCATIONS...WITH UPPER 30S LIKELY IN THE COLDEST INLAND
VALLEYS BY DAYBREAK SUNDAY.

A WARMING TREND WILL GET UNDERWAY ON SUNDAY AS AN UPPER RIDGE
BUILDS JUST OFFSHORE AND AS ONSHORE FLOW WEAKENS. WARMING WILL
CONTINUE INTO MONDAY AS THE UPPER RIDGE AXIS ALIGNS OVER CA. HIGH
TEMPERATURES ON MONDAY ARE FORECAST TO BE MOSTLY IN THE
70S...WITH LOWER TO MID 80S IN THE WARMEST INLAND AREAS. MONDAY IS
EXPECTED TO BE THE WARMEST DAY OF THE WEEK.

THE RIDGE IS FORECAST TO BE TRANSITORY...MOVING OFF TO OUR EAST BY
TUESDAY...AND WILL BE REPLACED BY AN UPPER TROUGH BY MIDWEEK.
COOLING WILL BEGIN ON TUESDAY AS THE UPPER TROUGH APPROACHES AND
ONSHORE FLOW INCREASES. AREAS OF COASTAL LOW CLOUDS AND FOG ARE
LIKELY TO DEVELOP BY TUESDAY MORNING. MOST COOLING ON TUESDAY
WILL BE IN COASTAL AREAS WHILE INLAND AREAS SHOULD REMAIN
RELATIVELY WARM. COOLER AIR WILL SPILL FARTHER INLAND BY
WEDNESDAY. THE TROUGH EXPECTED BY THE MIDDLE OF NEXT WEEK WILL BE
DRY AND NOT ESPECIALLY COOL. TEMPERATURES WILL REMAIN NEAR NORMAL
IN MOST AREAS.

THE LONGER RANGE MODELS SHOW NO INDICATION OF RAIN THROUGH AT
LEAST THE NEXT TEN DAYS (MAY 5TH). BASED ON CLIMATOLOGY...ODDS ARE
SLIM THAT WE WILL SEE ANOTHER SOAKING PRECIPITATION EVENT THIS
RAIN YEAR.

&&

.AVIATION...AS OF 10:45 PM PDT SATURDAY...SATELLITE SHOWS A FEW
SMALL PATCHES OF LOW CLOUDS AROUND THE AREA...OTHERWISE IT`S A MOSTLY
CLEAR EVENING. GRADUALLY DRIER NW WIND FLOW SUPPORTS VFR FOR THE
PERIOD EXCEPT LOCAL MVFR CIGS ARE STILL POSSIBLE BY EARLY SUNDAY
MORNING AS TEMPERATURES COOL.

VICINITY OF KSFO...WESTERLY WINDS HAVE SUBSIDED THROUGH THE
EVENING...BUT OCCASIONALLY HIGHER GUSTS TO NEAR 25 KNOTS ARE STILL
POSSIBLE THROUGH 10Z. VFR SHOULD HOLD OVERNIGHT INTO SUNDAY.

SFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...06Z TAFS CARRY SIMILAR FORECAST FROM
PREVIOUS INDICATING FEW-SCT CLOUD COVERAGE FOR THE OVERNIGHT HOURS.
W-NW WIND FLOW AND NOCTURNAL COOLING COULD INCREASE CLOUD COVERAGE
A LITTLE MORE THAN FORECAST TO PRODUCE PATCHY BKN-OVC COVERAGE AROUND
THE MONTEREY BAY BY MORNING. LOW CONFIDENCE FORECAST. MEDIUM TO HIGH
CONFIDENCE VFR FORECAST FOR SUNDAY.

&&

.MARINE...AS OF 8:23 PM PDT SATURDAY...GUSTY NORTHWEST WINDS WILL
CONTINUE INTO SUNDAY WITH ROUGH AND CHOPPY SEAS. WINDS WILL TURN
MORE NORTHERLY SUNDAY NIGHT THROUGH EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS AND THE PRESSURE GRADIENT STRENGTHENS NEAR CAPE
MENDOCINO.

&&

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

&&

$$

PUBLIC FORECAST: DYKEMA
AVIATION/MARINE: CANEPA

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