994
FXUS66 KMTR 150435
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
935 PM PDT THU AUG 14 2025
..NEW AVIATION
KEY MESSAGES
UPDATED AT 222 PM PDT THU AUG 14 2025
- A MARINE LAYER WILL BRING COASTAL DRIZZLE THE NEXT FEW
MORNINGS.
- TEMPERATURES WILL WARM SLIGHTLY THROUGH FRIDAY BEFORE RETURNING
BACK BELOW NORMAL THIS WEEKEND.
- STRONG NW WINDS WILL ARRIVE TO THE COAST TODAY AND SPREAD
INLAND FRIDAY - SATURDAY.
UPDATE
ISSUED AT 856 PM PDT THU AUG 14 2025
FORECAST REMAINS ON TRACK THIS EVENING WITH ELEVATED WINDS ALONG THE
COASTAL RANGES AND HIGHER ELEVATIONS OF NORTH AND EAST BAY
PERSISTING TONIGHT, INCREASING FURTHER FOR FRIDAY AFTERNOON/EVENING,
AND THEN STAYING BREEZY FOR SATURDAY. THE INCREASED ONSHORE WINDS
ARE DUE TO PERSISTENT UPPER LEVEL TROUGHING ACROSS OUR AREA WITH
NOWHERE TO GO DUE TO A LARGE AREA OF HIGH PRESSURE BUILDING ACROSS
THE CENTRAL US. COASTAL COMMUNITIES WILL SEE PERIODS OF DRIZZLE
OVERNIGHT INTO FRIDAY MORNING AS WELL.
DESPITE THE INCREASED ONSHORE FLOW, TEMPERATURES AWAY FROM THE
MARINE LAYER WILL BE AROUND 5-10 DEGREES WARMER FRIDAY THAN TODAY
WITH A SHORT WINDOW OF OFFSHORE FLOW DEVELOPING WITH HELP FROM THE
EKA-SFO GRADIENT CURRENTLY AROUND 5.5 MB, EXPECTED TO PEAK AROUND 6
MB TONIGHT AND FRIDAY MORNING.
SHORT TERM
ISSUED AT 217 PM PDT THU AUG 14 2025
(THIS EVENING THROUGH FRIDAY)
ANOTHER DAY OF LARGE TEMPERATURE SPREADS ACROSS THE BAY AREA AND
CENTRAL COAST FROM THE COASTLINE TO FAR INTERIOR LOCATIONS.
RATHER COMMON THIS TIME OF YEAR ACTUALLY. UPPER 50S/60S COAST TO
90S INLAND. WHILE WE'VE BEEN HYPING THE COOLDOWN IT'S STILL HOT
INLAND. IN FACT, A FEW INTERIOR LOCATIONS HAVEN'T DROPPED BELOW 90
DEGREES FOR DAYTIME HIGHS SINCE THE LAST WEEK OF JULY.
THE LOW CLOUDS LURKING ALONG THE COAST THIS AFTERNOON WILL MOVE
INLAND AGAIN TONIGHT. HOWEVER, THE EVOLUTION OF THE MARINE LAYER
TONIGHT WILL BE DIFFERENT THAN THE LAST FEW NIGHTS. WHILE THE
MARINE LAYER BEGINS TO MARCH INLAND IT WILL BE SLOWED/HAMPERED BY
SOME WEAK OFFSHORE FLOW AND ENTRAINMENT OF DRIER AIR. WEAK SURFACE
HIGH PRESSURE WILL CONTINUE TO BUILD ALONG THE OR/CA BORDER
RAMPING UP THE N-S GRADIENT TONIGHT. LARGER SCALE OFFSHORE
GRADIENT ALSO BEGINS TO RAMP UP TONIGHT AND EARLY FRIDAY.
THEREFORE, STRATUS COVERAGE WILL BE LESS FOR LOCATIONS NORTH OF
APPROX. HALF MOON BAY. AREAS SOUTH, WILL FEEL LESS INFLUENCE FROM
THE PRESSURE GRADIENTS SO IT WILL BE MORE OF THE SAME -
CLOUDS/DRIZZLE.
THE BIGGER WEATHER IMPACT ON FRIDAY CONTINUES TO BE THE WIND. A
LARGE SCALE UPPER LEVEL TROUGH WILL SETTLE IN REINFORCING
PRESSURE GRADIENTS. WEST TO NORTHWEST WINDS WILL INCREASE THOUGH
THE DAY FRIDAY AND PEAK FRIDAY AFTERNOON/EVENING. 20-40 MPH GUSTS
SEEM PLAUSIBLE WITH SOME PEAK GUSTS OF 50 MPH.
LONG TERM
ISSUED AT 217 PM PDT THU AUG 14 2025
(FRIDAY NIGHT THROUGH NEXT WEDNESDAY)
GRADIENTS RELAX OVER THE WEEKEND WITH DECREASING WINDS. EXPECT THE
MARINE LAYER TO BECOME MORE WIDESPREAD WITH DRIZZLE. COOLER
WEATHER WITH LONGWAVE BROAD TROUGHING CONTINUES THROUGH MONDAY. A
FOUR CORNERS RIDGE OF HIGH PRESSURE BEGINS TO NUDGE IN FROM THE
EAST BY TUESDAY KICKING OFF A WARMING TREND. ALL IN ALL, PRETTY
MELLOW LONG TERM FORECAST.
AVIATION
(06Z TAFS)
ISSUED AT 935 PM PDT THU AUG 14 2025
COASTAL STRATUS AND FOG /MVFR-IFR/ EXTEND SOUTHWARD FROM SAN
FRANCISCO. ONSHORE BREEZES WILL PREVAIL AT THE TERMINALS DURING
THE PERIOD, USHERING STRATUS AND FOG /MVFR-IFR/ INLAND TONIGHT AND
FRIDAY MORNING. BEST CHANCE FOR MVFR-VFR ALONG THE COAST IS LATE
FRIDAY MORNING INTO THE AFTERNOON. PATCHY LIGHT DRIZZLE IS
POSSIBLE TONIGHT AND FRIDAY MORNING AND AGAIN FRIDAY NIGHT AND
EARLY SATURDAY.
VICINITY OF SFO...VFR FORECAST TONIGHT THROUGH EARLY FRIDAY EVENING.
STRATUS /MVFR/ FORECAST TO RETURN BEGINNING MID FRIDAY EVENING. WEST
WIND 10 KNOTS TONIGHT AND FRIDAY MORNING, INCREASING TO 20 TO 30 KNOTS
FRIDAY AFTERNOON TO MID EVENING.
SFO BRIDGE APPROACH...SIMILAR TO SFO.
MONTEREY BAY TERMINALS...STRATUS AND FOG /MVFR-IFR/ CONDITIONS
DEVELOPING THIS EVENING AND PREVAILING TONIGHT AND FRIDAY MORNING.
CONDITIONS LIFTING TO MVFR-VFR BY LATE FRIDAY MORNING AND AFTERNOON.
ONSHORE WINDS 5 TO 15 KNOTS EXCEPT AFTERNOON AND EARLY EVENING GUSTS
TO 20 KNOTS.
MARINE
(TONIGHT THROUGH NEXT WEDNESDAY)
ISSUED AT 856 PM PDT THU AUG 14 2025
EXPECT WIDESPREAD HAZARDOUS CONDITIONS THROUGH SATURDAY DUE TO
STRONG NORTHWESTERLY BREEZES WITH GALE FORCE GUSTS ESPECIALLY FOR
THE OUTER WATERS AND COASTAL JET REGIONS OF POINT REYES AND POINT
SUR. THE BAYS WILL EXPERIENCE HAZARDOUS CONDITIONS FRIDAY AND
SATURDAY DUE TO FRESH TO STRONG WESTERLY BREEZES WITH NEAR-GALE
FORCE GUSTS. BREEZES WILL SLOWLY DIMINISH BY LATE WEEKEND WITH
ADDITIONAL EASING OCCURING EARLY NEXT WEEK. MODERATE TO ROUGH
SEAS WILL PREVAIL THROUGH SATURDAY FOR THE INNER WATERS AND OUTER
WATERS WITH MODERATE SEAS BY SUNDAY.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 3 PM TO 9 PM PDT FRIDAY FOR MRY BAY-SF
BAY N OF BAY BRIDGE.
GALE WARNING UNTIL 9 PM PDT FRIDAY FOR PT ARENA TO PT REYES 0-10
NM.
SMALL CRAFT ADVISORY UNTIL 9 PM PDT FRIDAY FOR PT REYES TO
PIGEON PT 0-10 NM.
SMALL CRAFT ADVISORY FROM 9 AM TO 9 PM PDT FRIDAY FOR PIGEON PT
TO PT PINOS 0-10 NM.
SMALL CRAFT ADVISORY UNTIL 9 AM PDT FRIDAY FOR PT PINOS TO PT
PIEDRAS BLANCAS 0-10 NM.
GALE WARNING FROM 9 AM TO 9 PM PDT FRIDAY FOR PT PINOS TO PT
PIEDRAS BLANCAS 0-10 NM.
GALE WARNING UNTIL 9 AM PDT FRIDAY FOR PIGEON PT TO PT PINOS 10-
60 NM-PT ARENA TO PT REYES 10-60 NM.
SHORT TERM...MM
LONG TERM....MM
AVIATION...CANEPA
MARINE...CANEPA
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, X, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
X.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page