897
FXUS66 KMTR 230943
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
243 AM PDT SAT MAY 23 2026
..NEW MARINE
KEY MESSAGES
UPDATED AT 1200 AM PDT SAT MAY 23 2026
- DIURNALLY DRIVEN ONSHORE WINDS DURING THE AFTERNOON AND EARLY
EVENING THROUGH THE EARLY PART OF NEXT WEEK
- GRADUAL COOLING TREND BEGINS TODAY WITH SEASONAL TEMPERATURES
FOR THE UPCOMING WEEKEND AND COOLER TEMPERATURES EARLY NEXT
WEEK
SHORT TERM
ISSUED AT 1200 AM PDT SAT MAY 23 2026
(TODAY AND TONIGHT)
EXTENSIVE STRATUS HAS DEVELOPED ALONG THE COAST AND HAS FLOWED INTO
THE NORTH BAY VALLEYS, THE NORTHERN PART OF THE EAST BAY, THE
MONTEREY BAY REGION, AND THE SALINAS VALLEY. READINGS FROM THE
BODEGA BAY PROFILER REVEAL A MARINE LAYER DEPTH OF AROUND 2000 FEET,
WHICH WOULD ALLOW FOR EXTENSIVE INLAND COVERAGE OF MARINE LAYER
STRATUS THIS MORNING AND WOULD LIMIT THE CLEARING OF STRATUS THROUGH
THE AFTERNOON HOURS. THE UPPER LEVEL PATTERN IS ALSO PROMOTING ZONAL
FLOW ACROSS THE STATE, REINFORCING THE COOLER AND MILDER CONDITIONS.
THUS, TODAY'S HIGHS ARE A LITTLE COOLER THAN YESTERDAY'S AS THE
INLAND VALLEYS REACH THE 70S AND THE LOWER 80S, WHILE AREAS NEAR THE
BAYS SEE HIGHS IN THE MIDDLE 60S TO LOWER 70S AND THE PACIFIC COAST
HOVERS IN THE UPPER 50S. BREEZY ONSHORE WINDS WILL DEVELOP DURING
THE AFTERNOON AND EVENING HOURS WITH GUSTS UP TO 20 MPH THROUGH
FAVORED GAPS AND PASSES.
LONG TERM
ISSUED AT 1200 AM PDT SAT MAY 23 2026
(SUNDAY THROUGH FRIDAY)
A SLIGHT COOLING MAY BE NOTICEABLE IN THE INLAND VALLEYS ON SUNDAY
WITH HIGH TEMPERATURES UP TO 5 DEGREES COOLER, BUT OTHERWISE
CONDITIONS WILL BE SIMILAR TO TODAY WITH EXTENSIVE MORNING STRATUS
AND BREEZY ONSHORE WINDS IN THE AFTERNOON AND EVENING HOURS. THE
COOLING TREND CONTINUES THROUGH THE EARLY PART OF NEXT WEEK WITH A
COLD FRONT ASSOCIATED WITH A DEEP UPPER LEVEL LOW EXPECTED TO SWEEP
THROUGH THE REGION SOMETIME ON TUESDAY, WITH TEMPERATURES IN THE 70S
ACROSS THE INTERIOR VALLEYS, THE MIDDLE TO UPPER 60S NEAR SAN
FRANCISCO BAY AND SANTA CRUZ, AND THE UPPER 50S TO LOWER 60S NEAR
THE PACIFIC COAST AND THE SOUTHERN MONTEREY BAY REGION. BREEZY WINDS
WILL DEVELOP ACROSS THE REGION WITH STRONG GUSTS THROUGH THE FAVORED
GAPS AND PASSES. ALTHOUGH THERE IS A VERY SLIGHT CHANCE (AROUND 10%
PROBABILITY) OF LIGHT SHOWERS OR DRIZZLE POPPING UP IN THE COASTAL
REGIONS, WIDESPREAD WETTING RAINS (RAIN TOTALS AT LEAST A TENTH OF
AN INCH) ARE NOT EXPECTED.
GRADUAL WARMING IS EXPECTED ONCE THE COLD FRONT PASSES ON WEDNESDAY,
WITH LINGERING NORTHERLY WINDS SPARKING SOME EARLY CONCERN FOR
ELEVATED FIRE WEATHER RISKS IN THE INTERIOR, ALTHOUGH IT'S A LITTLE
TOO EARLY TO PIN DOWN EXACT DETAILS AT THIS POINT. I'M NOT ONE
HUNDRED PERCENT SOLD ON WARMING ON THE SCALE THAT THE NBM MODEL
OUTPUT DEPICTS, BUT IT DOES APPEAR THAT TEMPERATURES IN THE 80S ARE
AT LEAST POSSIBLE FOR THE INLAND VALLEYS. BEYOND THE 7-DAY OUTLOOK,
THE FORECAST BECOMES MORE UNCERTAIN AS ENSEMBLE MEMBERS DIFFER ON
HOW QUICKLY THAT UPPER LEVEL LOW FILLS IN AND HOW THE PATTERN
EVOLVES WHEN IT DOES. THE CPC OUTLOOK LEANS TOWARDS TEMPERATURES
WARMER THAN THE SEASONAL AVERAGE (HIGHS AROUND 65 DEGREES FOR
DOWNTOWN SAN FRANCISCO) AND PRECIPITATIONS TOTALS NEAR THE SEASONAL
AVERAGE (RAIN TOTALS AROUND ONE OR TWO HUNDREDTHS OF AN INCH OF RAIN
PER DAY FOR DOWNTOWN SAN FRANCISCO) FOR THE LAST COUPLE DAYS OF MAY
INTO THE FIRST WEEK OF JUNE.
AVIATION
(06Z TAFS)
ISSUED AT 901 PM PDT FRI MAY 22 2026
THE STRATUS DECK HAS BEGUN ITS PUSH ONSHORE AND IS SET TO IMPACT ALL
TERMINALS AT SOME POINT (EXCEPT FOR SJC AND LVK) DURING THE TAF
PERIOD AS THE MARINE LAYER CONTINUES TO DEEPEN. WINDS REDUCE THROUGH
THE NIGHT, THUS ALLOWING MVFR-IFR CEILINGS TO DEVELOP. BY SATURDAY
LATE MORNING, WINDS WILL LOCALLY INCREASE WHICH WILL HELP TO MIX OUT
THE REMAINING LOW STRATUS IN THE AREA, CONFINING THE DECK RIGHT OFF
THE COASTLINE WHILE STILL IMPACTING HAF.
VICINITY OF SFO...MVFR CEILINGS WILL DEVELOP AROUND 09Z SATURDAY
(THOUGH THEY MAY ARRIVE A COUPLE HOURS EARLY) AS THE STRATUS
INTRUSION CONTINUES ONSHORE AND MARINE LAYER DEEPENS. THE LOW
CEILINGS BEGIN TO MIX OUT LATE SATURDAY MORNING AS MODERATE WINDS
DEVELOP THROUGH THE AFTERNOON, SHIFTING BACK TO VFR THROUGH THE TAF
PERIOD WITH THE POTENTIAL FOR ANOTHER ROUND OF MVFR CEILINGS
SATURDAY NIGHT.
SFO BRIDGE APPROACH...SIMILAR TO SFO.
MONTEREY BAY TERMINALS...AS WINDS DIMINISH OVERNIGHT, MVFR-IFR
CEILINGS WILL PREVAIL INTO LATE SATURDAY MORNING WITH SLIGHT IMPACTS
TO VISIBILITY. WINDS WILL INCREASE SATURDAY MORNING WHICH WILL MIX
OUT THE STRATUS DECK AND PUSH IT OFFSHORE, SHIFTING TO VFR
CONDITIONS FOR A SHORT PERIOD. THE MARINE LAYER IS EXPECTED TO PUSH
BACK ONSHORE SATURDAY EVENING FOR ANOTHER ROUND OF MVFR-IFR
CEILINGS.
MARINE
(TODAY THROUGH THURSDAY)
ISSUED AT 242 AM PDT SAT MAY 23 2026
MODERATE TO STRONG NORTHERLY BREEZES WILL GRADUALLY DECREASE THIS
MORNING OVER THE NORTHERN OUTER WATERS ALLOWING ROUGH SEAS TO
GRADUALLY SUBSIDE AS WELL. CONDITIONS REMAIN HAZARDOUS FOR SMALL
CRAFTS IN THE AFOREMENTIONED AREA THROUGH 9AM SATURDAY MORNING.
ELSEWHERE, WEST TO SOUTHWESTERLY WINDS WILL REMAIN LIGHT TO GENTLE
WITH MODERATE WAVE HEIGHTS. SEAS ABATE TO MODERATE HEIGHTS BY
MIDDAY SATURDAY AND THEN HOLD THROUGH EARLY TUESDAY MORNING. AN
INCOMING TROUGH IS SET TO APPROACH OUR WATERS LATE MONDAY NIGHT,
BRINGING STRONG NORTHWESTERLY WINDS AND BUILDING ROUGH SEAS.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 9 AM PDT THIS MORNING FOR PT ARENA TO
PT REYES 10-60 NM.
SHORT TERM...DIALH
LONG TERM....DIALH
AVIATION...NAVARRETE
MARINE...KR
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