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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
443 AM PDT SUN AUG 30 2015

.SYNOPSIS...A DRY UPPER TROUGH WILL REMAIN ANCHORED NEAR THE WEST
COAST THROUGH MOST OF THE WEEK. TEMPERATURES NEAR THE COAST WILL
BE NEAR SEASONAL NORMS...WHILE INLAND AREAS WILL GENERALLY BE
COOLER THAN NORMAL OVER THE NEXT SEVEN DAYS. NO RAIN IS EXPECTED.

&&

.DISCUSSION...AS OF 3:10 AM PDT SUNDAY...THANKS TO A COLD FRONT
THAT SWEPT ACROSS OUR REGION YESTERDAY DRIER AND COOLER AIR HAS
SETTLED ACROSS OUR AREA TODAY. MANY LOCATIONS ARE RUNNING 5 TO 10
DEGREES COOLER COMPARED TO YESTERDAY WHILE DEWPOINTS ARE ALSO
RUNNING 5 TO 10 DEGREES DRIER IN MANY SPOTS. SATELLITE PRODUCT
SHOWS PATCHY CLOUDS BOTH ALONG THE COAST...INTO THE EAST BAY AND
SANTA CLARA VALLEY. WOULD EXPECT THEM TO BURN-OFF FAIRLY FAST
LEADING TO MOSTLY SUNNY CONDITIONS BY AFTERNOON. HIGHS WILL BE IN
THE UPPER 60S TO UPPER 70S AT THE COAST WITH 80S FOR MOST INLAND
SPOTS. NORTHWESTERLY WINDS ARE EXPECTED TO INCREASE THROUGH THE
DAY. MANY SPOTS COULD SEE GUSTS OF AT LEAST 15 MPH BY THE
AFTERNOON WITH LOCALLY HIGHER VALUES EXPECTED.

OVERALL LOOKS LIKE A VERY QUIET WEEK FOR OUR REGION AS
SYNOPTICALLY A LONGWAVE TROF WILL BE CENTERED OVER THE WESTERN
CONUS WHILE A RIDGE OF HIGH PRESSURE REMAINS OVER THE EAST. TEMPS
WILL GENERALLY BE AT TO A BIT BELOW NORMAL INLAND WHILE COASTAL
SPOTS WILL BE AT OR SLIGHTLY ABOVE NORMAL. OVERNIGHT CLOUD COVER
IS EXPECTED TO INCREASE EACH NIGHT AS THE MARINE LAYER DEEPENS AND
THE ONSHORE FLOW SLIGHTLY INCREASES. THE STORM TRACK WILL STAY
WELL TO THE NORTH THROUGH THE PERIOD.

TEMPS WILL REBOUND A BIT BY THE END OF THE WEEK AS THE TROF SHIFTS
TO THE NORTH AND EAST. NO INDICATION OF RAIN RETURNING TO OUR
AREA THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. 

&&

.AVIATION...AS OF 4:30 AM PDT SUNDAY...STRATUS IS DISORGANIZED
AROUND THE AREA THIS MORNING. COOLER AIR ALOFT HAS SETTLED OVER
THE AREA AND THERE IS NO EVIDENCE OF A MARINE LAYER. AS A RESULT
CIGS OVER SFO AND THE APPROACH EXPECTED TO CLEAR EARLY. 

VICINITY OF KSFO...MVFR CIGS CLEARING AFT 17Z.
WEST WINDS TO 18-20 KT AFTER 20Z.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...PATCHY CIGS OVER MRY OTHERWISE
STRATUS IS STAYING OUT OF MRY BAY THIS MORNING. CIGS OVER MRY
SHOULD CLEAR AFT 15Z. 

&&

.BEACHES...AS OF 4:30 AM PDT SUNDAY...A LONG PERIOD WEST SWELL
HAS ARRIVED AND WILL CONTINUE TO ADVANCE ON WEST FACING BEACHES
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THESE LONG PERIOD
SWELLS CAN PRODUCE HAZARDOUS RIP CURRENTS THAT CAN QUICKLY PULL
SWIMMERS OUT TO SEA. THE HIGHEST RISK OF HAZARDOUS CONDITIONS WILL
BE THIS WEEKEND WHEN ONSHORE WINDS WEAKEN AND THE PERIOD INCREASES
FROM 15 TO 18 SECONDS. SWIMMERS CAUGHT IN A RIP CURRENT SHOULD
SWIM PARALLEL TO THE COAST TO ESCAPE THE RIP CURRENTS.

&&

.MARINE...AS OF 3:10 AM PDT SUNDAY...NORTHWEST WINDS WILL
INCREASE OVER THE COASTAL WATERS THROUGH THE WEEKEND. GUSTY WEST
WINDS ARE FORECAST SUNDAY AFTERNOON AND EVENING OVER THE NORTHERN
SAN FRANCISCO BAY. A LONG PERIOD WEST SWELL WILL CONTINUE TO MOVE
THROUGH THE WATERS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 PM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             SCA...SF BAY FROM 2 PM

&&

$$

PUBLIC FORECAST: BELL
AVIATION: W PI
MARINE: W PI/LARRY


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