958
FXUS66 KMTR 131654
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
954 AM PDT SUN JUL 13 2025
..NEW AVIATION
KEY MESSAGES
UPDATED AT 1229 AM PDT SUN JUL 13 2025
- TEMPERATURES NEAR TO SLIGHTLY BELOW SEASONAL AVERAGES WITH A
MORE NOTICEABLE COOLING TREND BEGINNING TUESDAY.
- LOCALIZED ELEVATED FIRE WEATHER THREAT CONTINUES ACROSS THE
HIGHER ELEVATIONS.
UPDATE
ISSUED AT 824 AM PDT SUN JUL 13 2025
COASTAL DRIZZLE WAS REPORTED AT A FEW SITES THIS MORNING WITH THE
GREATEST BEING AT DILLON BEACH WHERE 0.04" WAS REPORTED IN THE PAST
12 HOURS. OTHER LOCATIONS WHERE WE "TIPPED THE BUCKET" WERE IN THE
BAY AREA AROUND THE CITY OF SAN FRANCISCO, EAST BAY AT OAKLAND NORTH
RAWS, ANO NUEVO NATURAL RESERVE, COAST DAIRIES (SAN MATEO AND SANTA
CRUZ COUNTY COASTLINES), AND WHALE POINT ALONG THE BIG SUR
COASTLINE. HIGH CONFIDENCE FOR INLAND AREAS TO CLEAR OUT WITH
AFTERNOON TEMPERATURES REACHING TO AROUND THE SAME AS YESTERDAY. NO
UPDATES ARE ANTICIPATED THIS MORNING AS THE FORECAST REMAINS LARGELY
ON TRACK.
SHORT TERM
ISSUED AT 1229 AM PDT SUN JUL 13 2025
(TODAY AND TONIGHT)
SATELLITE IMAGERY SHOWS THE STRATUS LAYER BLOOMING INLAND INTO THE
SONOMA COUNTY VALLEYS, THE EAST BAY, SILICON VALLEY, THE MONTEREY
BAY REGION, AND THE SALINAS VALLEY. PROFILERS FROM BODEGA BAY, FORT
ORD, AND POINT SUR ARE DEPICTING A MARINE LAYER AROUND 1500 FT DEEP,
CONDUCIVE TO EXTENSIVE INLAND STRATUS DEVELOPMENT THROUGH THE REST
OF THE NIGHT, BEFORE THE CLOUDS RETREAT TO THE IMMEDIATE COAST
DURING THE MORNING. THE MARINE LAYER SHOULD COMPRESS SOMEWHAT
THROUGH THE DAY WITH A WEAK RIDGE AXIS SLOWLY RETROGRADING ACROSS
THE STATE, BUT SOME INLAND STRATUS IS STILL EXPECTED TONIGHT.
MORNING LOWS RANGE IN THE MIDDLE TO UPPER 50S FOR THE LOWER
ELEVATIONS, TO THE 60S AND LOWER 70S IN THE HIGHER ELEVATIONS. HIGH
TEMPERATURES REACH THE 80S INTO THE LOWER 90S INLAND, WITH HIGHS IN
THE UPPER 90S OR NEAR 100 EXPECTED AT THE SOUTHERN REACHES OF
MONTEREY AND SALINAS AND PLACES IN THE FAR INTERIOR BAY AREA
ADJACENT TO THE CENTRAL VALLEY. ELSEWHERE, THE BAYSHORE SHOULD SEE
HIGHS IN THE 70S AND LOWER 80S, DOWNTOWN SAN FRANCISCO SHOULD RISE
TO NEAR 66, AND THE PACIFIC COAST SHOULD SEE HIGHS IN THE UPPER 50S
TO LOWER 60S. ONSHORE WINDS WILL DEVELOP IN THE AFTERNOON AND
EVENING WITH GUSTS AS HIGH AS 25 MPH THROUGH FAVORED GAPS AND
PASSES AND WITHIN THE SALINAS VALLEY.
LOCALIZED ELEVATED FIRE WEATHER THREAT PERSISTS ACROSS AREAS ABOVE
AND INLAND OF THE MARINE LAYER'S INFLUENCE. THE COMBINATION OF DRY
DAYTIME HUMIDITIES OF AROUND 20-35%, POOR OVERNIGHT RECOVERIES OF 25-
40%, AND LOCALIZED GUSTS TO 25 MPH WILL BE THE MAIN FACTORS BEHIND
THE ELEVATED THREAT. HOWEVER, THE WINDS WILL REMAIN ONSHORE, LEADING
TO THE FIRE WEATHER THREAT BEING DIURNALLY DRIVEN, ESPECIALLY IN THE
FOOTHILLS WHERE LIGHTER WINDS AND GOOD OVERNIGHT RECOVERIES ARE
EXPECTED EACH NIGHT.
LONG TERM
ISSUED AT 1229 AM PDT SUN JUL 13 2025
(MONDAY THROUGH SATURDAY)
EXPECT MONDAY TO FEATURE SIMILAR CONDITIONS TO TODAY. LATE ON
MONDAY, A SHORTWAVE TROUGH, OR PERHAPS A WEAK CUTOFF LOW, DEVELOPS
INTO THE PACIFIC NORTHWEST, PUSHING THE RIDGE AXIS TOWARDS THE WEST
AND NORTH AND CAUSING A NOTICEABLE COOLING TREND TO BEGIN ON TUESDAY
AND LASTING FOR AT LEAST THE FOLLOWING TWO DAYS. HIGH TEMPERATURES
DROP INTO THE MIDDLE 70S TO MIDDLE 80S INLAND AND THE UPPER 60S TO
THE MIDDLE 70S ALONG THE BAYSHORE, WITH THE COAST REMAINING RATHER
STABLE AT THE UPPER 50S TO LOWER 60S.
TOWARDS THE END OF THE FORECAST PERIOD, THE FORECAST BECOMES A
LITTLE MORE UNCERTAIN. ENSEMBLE MODEL CLUSTER ANALYSIS POINTS TO
WEAK RIDGING (I.E. WARMER TEMPERATURES) AND WEAK TROUGHING (I.E.
COOLER TEMPERATURES) BY FRIDAY, WITH THE DIFFERENCES COMPOUNDING
THROUGH THE UPCOMING WEEKEND INTO THE EARLY PART OF THE FOLLOWING
WEEK, WHEN A SIGNIFICANT RIDGE AND A SIGNIFICANT TROUGH ARE POSSIBLE
ACROSS THE WESTERN UNITED STATES. WITH THE TWO SCENARIOS HAVING
NEARLY EQUAL PROBABILITIES, THERE IS NOT ENOUGH CONFIDENCE AT THIS
TIME TO DEVIATE FROM THE DEFAULT NBM FORECAST, WHICH DEPICTS A
GRADUAL WARMING TREND HEADING INTO THE UPCOMING WEEKEND. CPC
OUTLOOKS SUGGEST A SLIGHT LEAN TOWARDS TEMPERATURES ABOVE SEASONAL
AVERAGES IN THE 8-14 DAY PERIOD (JULY 20-26).
AVIATION
(18Z TAFS)
ISSUED AT 951 AM PDT SUN JUL 13 2025
CURRENTLY A MIXED BAG OF LIFR-VFR AT THE TERMINALS WITH VFR
EXPECTED SHORTLY AT ALL TERMINALS WITH THE EXCEPTION OF HAF WHICH
IS SLATED TO REMAIN SUB-VFR THROUGH THE TAF PERIOD. HIGH
CONFIDENCE IN ALL TERMINALS DETERIORATING TO SUB-VFR CONDITIONS
AGAIN TONIGHT AS THE PATTERN LARGELY REMAINS UNCHANGED. COASTAL
DRIZZLE WILL BE POSSIBLE DURING THE OVERNIGHT AND MORNING HOURS.
SMOKE FROM WILDFIRES BURNING IN NORTHERN CALIFORNIA WILL LIKELY
FILTER INTO THE REGION AND REDUCE SLIGHT RANGE VISIBILITIES.
VICINITY OF SFO...CURRENTLY VFR WITH NORTHWESTERLY FLOW. WESTERLY
FLOW WILL RETURN ONCE THE SEA BREEZE KICKS IN THIS AFTERNOON. HIGH
CONFIDENCE IN SUB-VFR CEILINGS RETURNING TONIGHT, LIKELY ON THE CUSP
OF IFR/MVFR.
SFO BRIDGE APPROACH...THE APPROACH STILL HAS SOME LOW STRATUS THIS
MORNING, BUT THAT SHOULD EVAPORATE VERY QUICKLY. LOW STRATUS CLOUDS
WILL BEGIN TO FILTER IN THROUGH THE GOLDEN GATE GAP BY 01Z WITH
VISUALS LIKELY BEING IMPACTED THROUGH 18Z MONDAY.
MONTEREY BAY TERMINALS...CURRENTLY LIFR WITH WESTERLY FLOW AT MRY
AND IFR AND CALM AT SNS. BOTH TERMINALS ARE EXPECTED TO IMPROVE TO
VFR SHORTLY WITH STRATUS STICKING TO THE COAST DURING THE DAY. HIGH
CONFIDENCE IN LIFR CEILINGS RETURNING TO BOTH TERMINALS TONIGHT.
MARINE
(TODAY THROUGH FRIDAY)
ISSUED AT 824 AM PDT SUN JUL 13 2025
LOCALIZED HAZARDOUS MARINE CONDITIONS IN THE FORM OF STRONG
NORTHERLY BREEZES AND VERY ROUGH SEAS WILL BE PRESENT MONDAY AND
TUESDAY FOR THE NORTHERN OUTER WATERS. ASIDE FROM THAT, A GENTLE
TO MODERATE BREEZE WITH MODERATE TO ROUGH SEAS WILL PREVAIL
THROUGH THURSDAY.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 3 PM MONDAY TO 3 AM PDT TUESDAY FOR PT
ARENA TO PT REYES 10-60 NM.
SHORT TERM...DIALH
LONG TERM....DIALH
AVIATION...SARMENT
MARINE...SARMENT
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