866
FXUS66 KMTR 231132
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
432 AM PDT FRI OCT 23 2026
..NEW AVIATION, MARINE
KEY MESSAGES
UPDATED AT 1231 AM PDT FRI OCT 23 2026
- GUSTY OFFSHORE FLOW ACROSS THE NORTH BAY INTERIOR MOUNTAINS
TONIGHT THROUGH SATURDAY MORNING
- BELOW NORMAL TEMPERATURES TODAY, INCREASE TO NEAR NORMAL FOR
THE WEEKEND
- COASTAL FLOODING DUE TO FULL MOON AND THERMAL EXPANSION THIS
WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT WEEK
SHORT TERM
ISSUED AT 1231 AM PDT FRI OCT 23 2026
(TODAY AND TONIGHT)
THE FIRST RAINFALL EVENT OF THE NEW WATER YEAR IS WINDING DOWN,
AFTER BRINGING WIDESPREAD BENEFICIAL WETTING RAINFALL ACROSS OUR
ENTIRE FORECAST AREA. POCKETS OF SCATTERED LIGHT RAIN ACROSS THE
CENTRAL COAST REMAINS POSSIBLE THROUGH SUNRISE THIS MORNING.
LINGERING CLOUDS AND MOISTURE WILL HELP KEEP TEMPERATURES BELOW
NORMAL TODAY BEFORE WARMING TO NEAR NORMAL FOR THE WEEKEND. A
DEVELOPING BURST OF OFFSHORE FLOW WILL PRODUCE GUSTY WINDS ACROSS
THE NORTH BAY INTERIOR MOUNTAINS THIS EVENING THROUGH THE MORNING
HOURS SATURDAY AS A RELATIVELY WEAK AND PROGRESSIVE 'INSIDE SLIDER'
TROUGH PASSES SOUTH THROUGH THE CENTRAL VALLEY TODAY. A MUCH DRIER
AIRMASS WILL BUILD IN BEHIND THE TROUGH WITH PWATS FALLING FROM
AROUND 0.75" DURING THE DAY TODAY, TO BELOW 0.50" AFTER SUNSET. THE
STRONGEST WIND GUSTS WILL OCCUR ABOVE 2500FT, UP TO 45 MPH WITH
LITTLE VERTICAL GRADIENT FORCING TO HELP TRANSLATE STRONGER WINDS
TO LOWER LYING AREAS.
LONG TERM
ISSUED AT 1231 AM PDT FRI OCT 23 2026
(SATURDAY THROUGH THURSDAY)
THE WEEKEND WILL SEE A RETURN OF TEMPERATURES TO NEAR NORMAL FOR
THIS TIME OF YEAR AND BRIGHT SUNNY SKIES DUE TO THE DRIER AIRMASS.
PROGRESSIVE LOW AMPLITUDE RIDGING THIS WEEKEND WILL GIVE WAY TO AN
UPPER LEVEL LOW DROPPING SOUTH OUT OF THE PNW FOR THE BEGINNING OF
NEXT WEEK. OVERALL, CONSENSUS IN THE SYNOPTIC PATTER BEGINS TO
DIVERGE FROM THERE, BUT EITHER WAY TEMPERATURES APPEAR TO REMAIN
RIGHT AROUND NORMAL WITH SOME PLEASANT FALL DAYS THROUGH THE
EXTENDED FORECAST. MINOR COASTAL FLOODING DUE TO LUNAR PHASE AND
THERMAL EXPANSION IS POSSIBLE AT NORMAL TROUBLE SPOTS.
AVIATION
(12Z TAFS)
ISSUED AT 417 AM PDT FRI OCT 23 2026
MVFR-IFR MOST SITES WITH THE EXCEPTION OF STS WHERE FOG AND LIFR
CONDITIONS HAVE DEVELOPED. EXPECT MVFR CIGS TO PERSIST THROUGH
LATE MORNING WITH GUIDANCE SHOWING CLEARING BETWEEN 17-20Z.
PERSISTENT CLOUD COVER SHOULD PREVENT FOG FROM REACHING APC THIS
MORNING WITH MODERATE CONFIDENCE THAT CIGS WILL STAY ON THE
IFR/MVFR BORDER. MODERATE TO HIGH CONFIDENCE IN VFR CONDITIONS
THIS AFTERNOON THROUGH THE END OF THE TAF PERIOD AS A MUCH DRIER
AIR MASS MOVES IN IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW.
WINDS RETURN TO A MORE TYPICAL PATTERN WITH BREEZY ONSHORE WINDS
DURING THE AFTERNOON/EVENING AND LIGHTER, VARIABLE TO OFFSHORE
WINDS OVERNIGHT.
VICINITY OF SFO...MVFR CIGS PERSIST THROUGH LATE MORNING WITH VFR
CONDITIONS/CLEAR SKIES EXPECTED THIS AFTERNOON THROUGH THE END OF
THE TAF PERIOD. MODERATE ONSHORE WINDS PEAKING AROUND 15 KNOTS ARE
EXPECTED THIS AFTERNOON BEFORE WINDS WEAKEN OVERNIGHT AND
GRADUALLY BECOME MORE EASTERLY.
SFO BRIDGE APPROACH...PATCHY CLOUD COVER MAY LINGER OVER THE
SOUTHERN SF BAY LONGER THAN OVER THE SFO TERMINAL THIS MORNING.
GUIDANCE SUGGESTS IT COULD TAKE LONGER FOR CLOUD COVER TO CLEAR
ACROSS THE SOUTH BAY/SOUTHERN SF BAY AS ADDITIONAL ROUNDS OF LOW
LEVEL CLOUDS PUSH IN FROM THE INTERIOR.
MONTEREY BAY TERMINALS...MVFR THROUGH LATE MORNING. MODERATE
CONFIDENCE THAT CIGS WILL CLEAR AROUND 19Z WITH VFR CONDITIONS TO
PREVAIL THROUGH THE REMAINDER OF THE DAY. ONSHORE WINDS TO AROUND
10-12 KNOTS EXPECTED DURING THE AFTERNOON WITH LIGHTER, VARIABLE
TO OFFSHORE WINDS EXPECTED OVERNIGHT.
MARINE
(TODAY THROUGH WEDNESDAY)
ISSUED AT 417 AM PDT FRI OCT 23 2026
LOW CHANCE FOR ISOLATED SHOWERS ACROSS THE COASTAL WATERS THROUGH
LATE MORNING BEFORE DRIER WEATHER RETURNS LATE TODAY. FRESH TO
LOCALLY STRONG NORTHERLY WINDS CONTINUE WITH NEAR GALE FORCE TO
GALE FORCE GUSTS POSSIBLE ACROSS THE FAR NORTHERN OUTER WATERS.
WINDS DECREASE BY EARLY SATURDAY WITH A MODERATE NORTHERLY BREEZE
PREVAILING THROUGH THE UPCOMING WEEK. ROUGH SEAS ARE EXPECTED
TODAY AND TOMORROW ACROSS THE OUTER WATERS WITH WAVE HEIGHTS
PEAKING BETWEEN 10 TO 13 FEET. MODERATE SEAS PREVAIL SUNDAY
THROUGH MUCH OF NEXT WEEK.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 9 AM PDT THIS MORNING FOR PT ARENA TO
PT REYES 0-10 NM-PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 PM PDT THIS
EVENING FOR PIGEON PT TO PT PINOS 0-10 NM-PT PINOS TO PT
PIEDRAS BLANCAS 0-10 NM.
SMALL CRAFT ADVISORY UNTIL 9 AM PDT SATURDAY FOR PT ARENA TO PT
REYES 10-60 NM.
SMALL CRAFT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR PIGEON PT
TO PT PINOS 10-60 NM.
SHORT TERM...JM
LONG TERM....JM
AVIATION...KENNEDY
MARINE...KENNEDY
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