751
FXUS66 KMTR 142314
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
414 PM PDT FRI AUG 14 2026
..NEW AVIATION, MARINE
KEY MESSAGES
UPDATED AT 156 PM PDT FRI AUG 14 2026
- PATCHY COASTAL DRIZZLE LATE TONIGHT INTO SATURDAY MORNING
- GRADUAL WARMING TREND THIS WEEKEND INTO NEXT WEEK, BUT BELOW
NORMAL TEMPERATURES WILL PREVAIL
- POOR OVERNIGHT HUMIDITY RECOVERY ACROSS THE SANTA LUCIA AND
DIABLO RANGES RESUME EARLY NEXT WEEK
SHORT TERM
ISSUED AT 156 PM PDT FRI AUG 14 2026
(THIS EVENING THROUGH SATURDAY NIGHT)
IMPROVING SKY CONDITIONS WILL PERSIST THIS AFTERNOON AS DAYTIME
HEATING AND MIXING GRADUALLY ERODES THE MARINE STRATUS FROM EAST
TO WEST. A COUPLE OF PERSISTENT EDDIES ACROSS BODEGA BAY WILL
CONTINUE TO SEND A FEED OF STRATUS INTO THE NORTH BAY. CONFIDENCE
STILL REMAINS HIGH THAT CLEARING WILL CONTINUE HERE AND WE'LL SEE
THE MAXT FORECAST REMAIN ON TRACK. WINDS CONTINUE TO CLIMB ACROSS
SOME OF THE FAVORED REGIONS OF THE EAST BAY AND GUSTS TO NEAR 40
MPH ARE PROBABLE HERE. FUELS ACROSS THIS AREA ARE DRY AND THERE
DOES REMAIN SOME FIRE GROWTH POTENTIAL HERE (PENDING AN IGNITION).
BROAD TROUGHING ALOFT IN TANDEM WITH THE SFO-SAC/SFO-SMK
GRADIENTS INCREASING TO AROUND 3MB SHOULD SPELL A RETURN OF MARINE
STRATUS ACROSS MOST OF THE AREA, WITH THE EXCEPTION BEING SOME
ELEVATIONS ABOVE 3000 FEET. WHILE OVERNIGHT HUMIDITY RECOVERY INTO
SATURDAY WILL AGAIN CLIMB ABOVE 60% FOR MANY LOCALES, SOME OF THE
PEAKS ACROSS THE SANTA LUCIA AND DIABLO RANGES, AS WELL AS THE
SANTA CRUZ MOUNTAINS, EAST BAY HILLS AND NORTH BAY MOUNTAINS MAY
ONLY EXPERIENCE MAX RH AROUND 40%. THIS WILL HOPEFULLY HELP AT
LEAST MODULATE ANY ONGOING FIRE ACTIVITY ALONG THE CENTRAL COAST
DURING THE OVERNIGHT HOURS, OUTSIDE OF THE HIGHEST PEAKS.
THE AFOREMENTIONED TROUGHING IN PLACE WILL INSTIGATE OROGRAPHIC
ASCENT ALONG THE COAST AND COASTAL RANGES LATE TONIGHT AND INTO
THE PRE-DAWN HOURS ON SATURDAY. FORECAST SOUNDINGS SHOW A MOIST
PLANETARY BOUNDARY LAYER ALONG WITH STEEP LOW LEVEL LAPSE RATES
CAPPED BY A NEARLY 20C TEMPERATURE INVERSION. THIS SHOULD PROMOTE
POCKETS OF DRIZZLE WHICH MAY TRANSLATE TO SLICK ROAD CONDITIONS
AND REDUCED VISIBILITY THROUGH ABOUT 18 UTC ON SATURDAY. BE SURE
TO EXERCISE CAUTION IF COMMUTING.
SATURDAY WILL START OUT GLOOMY AND WHILE TROUGHING WILL PERSIST,
THE AMPLITUDE OF THE WAVE APPEARS A LITTLE LESS THAN TODAY
(FRIDAY). THIS SHOULD TRANSLATE TO AN EARLIER CLEARING TIME AND A
POTENTIAL FOR GREATER INSOLATION AND THUS WARMER CONDITIONS.
TEMPERATURES WILL STILL BE RUNNING A GOOD 5 TO 15 DEGREES BELOW
NORMAL ACROSS THE AREA, BUT IT'LL BE A LARGELY PLEASANT DAY.
LONG TERM
ISSUED AT 156 PM PDT FRI AUG 14 2026
(SUNDAY THROUGH NEXT THURSDAY)
AS WE PROGRESS INTO THE LATTER HALF OF THE WEEKEND AND INTO NEXT
WEEK, WE'LL MAINTAIN GENERALLY SOUTHWESTERLY FLOW ALOFT. WHILE THE
ONSHORE FLOW WILL REMAIN IN PLACE, THE TROUGH AXIS WILL BE
DISPLACED FATHER WEST WHICH MAY EQUATE TO LESS IN THE WAY OF
SYNOPTIC SCALE ASCENT ACROSS OUR AREA. WHILE I CANNOT COMPLETELY
DISCOUNT THE POTENTIAL FOR PATCHY DRIZZLE, I'LL FORGO MENTIONING
DZ SUNDAY AND ONWARD AT THIS TIME. THE MARINE LAYER MAY NOT BE
QUITE AS DEEP AT TIMES NEXT WEEK AND IN FACT, THE DETERMINISTIC
GUIDANCE SUGGEST A RETURN TO POOR OVERNIGHT HUMIDITY RECOVERY (MAX
RH BETWEEN 20% AND 40%) ACROSS THE HIGHER TERRAIN OF THE SANTA
LUCIA AND DIABLO RANGES AS WELL AS THE EAST BAY/SANTA CLARA HILLS
AND PORTIONS OF THE NORTH BAY MOUNTAINS. FORTUNATELY, THERE
DOESN'T APPEAR TO BE A STRONG SIGNAL FOR WINDS (OUTSIDE OF THE
FAVORED GAPS AND PASSES), THOUGH FAVORABLE ALIGNMENT OF FUELS
(WHICH STILL REMAIN DRY) AND TERRAIN COULD SUPPORT SOME FIRE
GROWTH POTENTIAL.
WHILE THE TROUGH AXIS WILL REMAIN A BIT FARTHER TO THE WEST,
ENOUGH SOUTHWESTERLY FLOW SHOULD KEEP THE PACIFIC SOUTHWEST RIDGE
IN CHECK. WHILE THE MULTI-MODEL ENSEMBLE MEAN KEEPS THE HEART OF
THE RIDGE ANCHORED ACROSS SOUTHERN NEW MEXICO AND ADJACENT
PORTIONS OF WEST TEXAS, THERE ARE SOME SOLUTIONS WHICH PLACE THE
RIDGE AXIS CLOSER TO THE FOUR CORNERS. SHOULD THIS SOLUTION
VERIFY, COMPRESSION OF THE MARINE LAYER COULD MEAN THAT THE
CURRENT MAXT FORECAST TOWARD THE END OF THE LONG TERM PERIOD WILL
NEED TO BE ADJUSTED UPWARD.
AVIATION
(00Z TAFS)
ISSUED AT 414 PM PDT FRI AUG 14 2026
GENERALLY MVFR STRATUS PERSISTS ACROSS THE COASTAL REGIONS WITH A
PLUME CONTINUING TO FLOW THROUGH THE GOLDEN GATE. MODERATE AND GUSTY
ONSHORE WINDS WILL CONTINUE INTO THE EVENING HOURS, WHEN WINDS
BECOME LIGHT AND THE STRATUS WILL BEGIN EXPANDING OVER ALL OF THE
INTERIOR TERMINALS. STRATUS WILL CLEAR OUT ACROSS THE INLAND
TERMINALS LATE SATURDAY MORNING INTO THE EARLY AFTERNOON, WITH
BREEZY ONSHORE WINDS RESUMING IN THE AFTERNOON. BEYOND THE TAF
PERIOD, A BUILDING THERMAL RIDGE WILL LIKELY COMPRESS THE MARINE
LAYER.
VICINITY OF SFO... CLOUDS FLOWING OVER THE SAN BRUNO GAP WILL LIKELY
RESULT IN PULSES OF MVFR CEILINGS AT THE TERMINAL. OTHERWISE
CONDITIONS REMAIN GENERALLY VFR WITH MODERATE AND GUSTY WEST WINDS
THROUGH THE EVENING HOURS. MVFR STRATUS WILL DEVELOP LATE THIS
EVENING, WITH CLEARING EXPECTED SOMETIME DURING THE LATE MORNING OR
EARLY AFTERNOON HOURS ON SATURDAY. CONFIDENCE IN THE CLEARING TIME
IS LOW AT THIS TIME. BREEZY WEST-NORTHWEST WINDS WILL RESUME
SATURDAY AFTERNOON, WITH MODERATE CONFIDENCE IN STRATUS RETURNING IN
THE EVENING A COUPLE OF HOURS BEFORE THE END OF THE TAF PERIOD.
SFO BRIDGE APPROACH... SIMILAR TO SFO.
MONTEREY BAY TERMINALS... VFR THROUGH THE NEXT FEW HOURS BEFORE MVFR
CEILINGS RETURN TO THE TERMINALS IN THE EVENING HOURS. NORTHWEST
WINDS WILL REMAIN MODERATE AND BREEZY THROUGH THE EVENING, BECOMING
LIGHT OVERNIGHT BEFORE RESUMING SATURDAY AFTERNOON. STRATUS WILL
CLEAR OUT FROM SNS LATE ON SATURDAY MORNING WHILE MODERATE
CONFIDENCE THAT MRY REMAINS SOCKED IN THROUGH THE TAF PERIOD.
MARINE
(TONIGHT THROUGH NEXT WEDNESDAY)
ISSUED AT 414 PM PDT FRI AUG 14 2026
GENTLE TO MODERATE NORTHWEST WINDS WILL CONTINUE THROUGH EARLY
NEXT WEEK. SEAS WILL CONTINUE TO SUBSIDE AND BECOME MODERATE IN
RESPONSE. A LONG PERIOD SOUTHERLY SWELL OF ABOUT 16 TO 18 SECONDS
APPROACHES THE COAST TONIGHT INTO SUNDAY. WINDS WILL FRESHEN
EARLY TO MID NEXT WEEK, CAUSING SEAS TO BUILD UP TO 9 FEET.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...NONE.
SHORT TERM...BAIN
LONG TERM....BAIN
AVIATION...DIALH
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