267
FXUS66 KMTR 040513
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
913 PM PST SAT JAN 3 2026
..NEW AVIATION
KEY MESSAGES
UPDATED AT 117 PM PST SAT JAN 3 2026
- HIGH ASTRONOMICAL TIDES COMBINED WITH STORM SURGE WILL BRING
SUBSTANTIAL TIDAL FLOODING THROUGH SUNDAY
- CHANCE OF THUNDERSTORMS THROUGH THE WEEKEND
- HAZARDOUS BEACH CONDITIONS SUNDAY
- DAILY RAIN SHOWERS EXPECTED THROUGH MONDAY
UPDATE
ISSUED AT 835 PM PST SAT JAN 3 2026
ISOLATED TO SCATTERED SHOWERS PERSIST ACROSS THE BAY AREA AND
CENTRAL COAST, WITH AN ORGANIZED LINE LURKING OFF THE NORTH BAY
COASTLINE COMING ONSHORE JUST NORTH OF THE MENDOCINO-SONOMA COUNTY
LINE. LATEST HIGH RESOLUTION MODEL OUTPUT HAS MORE WIDESPREAD
RAINFALL DEVELOPING THROUGH THE DAY SUNDAY, WHICH IS PRETTY HIGH
CONFIDENCE AT THIS POINT. HOWEVER, WITH THE TENDENCY OF THE LAST
COUPLE OF SYSTEMS TO SLOW DOWN AND UNDER PERFORM AS THEY APPROACH
THE REGION, CONFIDENCE IN SPECIFIC TIMING AND LOCATION OF THE
MOST INTENSE RAIN IS LOW. THE INCOMING SHIFT WILL CONTINUE TO
MONITOR DEVELOPMENTS IN THE SYSTEM THROUGH THE NIGHT.
DIALH
SHORT TERM
ISSUED AT 117 PM PST SAT JAN 3 2026
(THIS EVENING THROUGH SUNDAY)
IT HAS BEEN A FAIRLY ACTIVE DAY FOR OUR NEIGHBORING OFFICES TO
THE NORTH AND SOUTH THIS MORNING AND EARLY AFTERNOON! HOWEVER, WE
HAVE HAD SEVERAL REPORTS OF SHALLOW LANDSLIDES IN THE NORTH BAY
DUE TO SATURATED SOILS AS RAIN SHOWERS CONTINUE AT TIMES ACROSS
THE REGION. ADDITIONALLY, WE HAVE HAD SEVERAL REPORTS OF COASTAL
FLOODING DUE TO THE KING TIDES. THE SAN FRANCISCO TIDAL GAUGE
REACHED 2.56 FT ABOVE GROUND LEVEL AT AROUND 10:26 AM SATURDAY
MORNING, THUS VERIFYING THE COASTAL FLOOD WARNING FOR THE SAN
FRANCISCO AND SAN PABLO BAYS.
LOOKING AHEAD, THERE REMAINS A CHANCE FOR HEAVY SHOWERS AND
THUNDERSTORMS PARTICULARLY ACROSS THE NORTH BAY WHERE UP TO 700
J/KG OF SURFACE BASED CAPE IS FORECAST THROUGH EARLY AFTERNOON. IF
WE CAN MANAGE TO FIND A TRIGGERING MECHANISM TO TAP INTO THIS
INSTABILITY, THERE WOULD BE A LOW END POTENTIAL FOR SEVERE
THUNDERSTORM. HOWEVER, THERE HASN'T BEEN ANY THUNDERSTORMS OVER
THE LAND AS OF THIS WRITING. ELSEWHERE, EXPECTING PASSING SHOWERS
AND ISOLATED THUNDERSTORMS OFF AND ON THROUGH THE AFTERNOON AND
EARLY EVENING AHEAD OF OUR NEXT FRONTAL SYSTEM SET TO ARRIVE EARLY
SUNDAY MORNING. THE SPC HAS A GENERAL MENTION OF THUNDERSTORMS
ACROSS THE ENTIRE REGION ON SUNDAY, WITH FORECAST SURFACE BASED
CAPE OF UP TO 400 J/KG. WHILE THE THREAT FOR RIVER FLOODING
CONTINUES TO BE VERY LOW, THE USGS IS REPORTING SATURATED SOILS
ACROSS MUCH OF THE BAY AREA. AS SUCH, ANY HEAVIER RAIN SHOWERS
AND/OR THUNDERSTORMS WOULD INCREASE THE POTENTIAL FOR SHALLOW
LANDSLIDES. THIS ALSO WOULD RESULT IN RAPID RISES OF SMALL
CREEKS/STREAMS ACROSS THE ENTIRE REGION.
LONG TERM
ISSUED AT 117 PM PST SAT JAN 3 2026
(SUNDAY NIGHT THROUGH NEXT FRIDAY)
THERE IS MORE UNCERTAINTY WITH REGARDS TO SHOWERS AND POTENTIAL
THUNDERSTORMS FOR MONDAY AND INTO TUESDAY. A NEWLY DEVELOPED
MID/UPPER LEVEL CUT OFF LOW PRESSURE SYSTEM WITHIN THE BROADER
TROUGH MAY VERY WELL STAY FAR ENOUGH OFFSHORE AND NOT PROVIDE MUCH
IN THE WAY OF RAINFALL. THIS IS BASED OFF OF SOME OF THE
CONVECTIVE ALLOWING MODELS (CAMS). HOWEVER, THE GFS/ECMWF/CMC ALL
SHOW ANOTHER AROUND OF SHOWERS/THUNDERSTORMS MOVING ACROSS MOVING
ONSHORE MONDAY MORNING AND CONTINUING THROUGH THE
AFTERNOON/EVENING AS THE CUT OFF LOW SLIDES SOUTH JUST OFF OF THE
BAY AREA AND CENTRAL COAST. WE ARE ALSO LEANING ON THE GLOBAL
MODELS FOR THIS AND STILL ARE ADVERTISING ANOTHER AROUND OF RAIN
SHOWERS MONDAY AND INTO TUESDAY. COOL, UNSETTLED CONDITIONS LOOK
TO PERSIST THROUGH MIDWEEK BEFORE A BUILDING RIDGE OF HIGH
PRESSURE DEVELOPS LATE IN THE WEEK BRINING A RETURN TO DRY
CONDITIONS. COLDER OVERNIGHT LOW TEMPERATURES ARE ALSO LOOKING
MORE LIKELY FOR LATE IN THE UPCOMING WEEK.
AVIATION
(06Z TAFS)
ISSUED AT 909 PM PST SAT JAN 3 2026
SCATTERED LIGHT SHOWERS CONTINUE WITH MODERATE TO BREEZY SOUTHERLY
WINDS. SHOWER ACTIVITY INCREASES INTO THE NIGHT, THEN BECOME MORE
WIDESPREAD WITH A ANOTHER FRONTAL BOUNDARY SUNDAY MORNING AND INTO
THE AFTERNOON. EXPECT REDUCED VISIBILITIES ALONG THE LEADING EDGE OF
THE FRONT FROM INCREASED RAIN RATES, WITH VISIBILITIES STRUGGLING TO
RECOVER IN THE POST-FRONTAL ENVIRONMENT BETWEEN LINGERING SHOWERS
AND POCKETS OF FOG AND MIST TRAPPED IN THE VALLEYS. SHOWER ACTIVITY
REDUCES INTO LATE SUNDAY AFTERNOON AND EVENING, BUT SLIGHT CHANCES
LOOK TO LAST THROUGH THAT NIGHT AND REBUILD AGAIN MONDAY MORNING.
VICINITY OF SFO...LIGHT SCATTERED SHOWERS CONTINUE TO MOVE THROUGH
THE AREA WITH BREEZY SOUTHERLY WINDS. WINDS REDUCE INTO THE NIGHT,
WHILE SHOWER ACTIVITY INCREASES SLIGHTLY. THIS WILL CAUSE SLIGHT
REDUCTIONS IN VISIBILITIES. RAIN CHANCES BUILD AGAIN IN THE MID
MORNING AS THE NEXT FRONT ARRIVES, WITH PERSISTENT SHOWERS EXPECTED
IN THE WAKE OF THE FRONT THROUGH THE AFTERNOON. RAIN CHANCES REDUCE
AGAIN INTO SUNDAY EVENING, BUT SPOTTY SHOWERS CONTINUE TO BE
POSSIBLE. MORE WIDESPREAD AND PERSISTENT RAIN IS EXPECTED TO RETURN
MID-MORNING ON MONDAY.
SFO BRIDGE APPROACH...SIMILAR TO SFO.
MONTEREY BAY TERMINALS...LIGHT SHOWERS ARE MOSTLY STAYING ALONG THE
SANTA LUCIAS AND ALONG THE BIG SUR COAST, BUT A FEW WILL PASS NEAR
THE TERMINALS THROUGH THE EVENING. CHANCES FOR RAIN CONTINUE THROUGH
THE NIGHT AND INCREASE AHEAD OF THE NEXT FRONT INTO THE MID MORNING.
RAIN RATES, AND SOME TRAPPED MOISTURE WILL CAUSE REDUCTIONS IN
VISIBILITIES AS THE FRONT MOVES THROUGH, AND IN THE POST-FRONTAL
ENVIRONMENT. WINDS AND RAIN CHANCES REDUCE LATE SUNDAY AFTERNOON
WITH CLOUD COVER BEGINNING TO SCATTER.
MARINE
(TONIGHT THROUGH NEXT FRIDAY)
ISSUED AT 835 PM PST SAT JAN 3 2026
SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS CONTINUE THROUGH THE
REST OF THE WEEKEND. BREEZY TO GUSTY WINDS LINGER THROUGH THE REST
OF THE WEEKEND ACROSS THE WATERS, WITH HAZARDOUS SWELLS FOR
SMALLER CRAFT AT 12 TO 16 FEET THAT ABATE EARLY NEXT WEEK. EXPECT
MOSTLY LIGHT WINDS AND SEAS INTO THE WORK WEEK WITH SOME SHOWERS
ON MONDAY. WINDS AND SEAS BUILD AGAIN INTO THE LATE WEEK.
BEACHES
ISSUED AT 117 PM PST SAT JAN 3 2026
A COASTAL FLOOD ADVISORY IS IN EFFECT FOR THE SAN FRANCISCO BAY,
SAN PABLO BAY, PACIFIC COAST, AND MONTEREY BAY THROUGH SUNDAY.
PERIGEAN SPRING TIDES (KING TIDES) WILL IMPACT THE REGION THROUGH
SUNDAY. THIS IS DUE TO THE COMBINATION OF THE FULL MOON ON 1/3,
LUNAR PERIGEE ON 1/1, AND PERIHELION ON 1/3. IN OTHER WORDS THE
EARTH, SUN AND MOON ARE LINED UP AND CLOSE TO EACH OTHER. IN
ADDITION TO THE HIGH ASTRONOMICAL TIDE, THERE ARE SEVERAL SYSTEM
SET TO BRING MODERATE SOUTHERLY WINDS, GENERATING SOME STORM
SURGE. THE COMBINATION OF THESE FACTORS WILL BRING MINOR TO
MODERATE COASTAL FLOODING TO THE LOW-LYING AREAS NEAR SHORELINES
AND TIDAL WATERWAYS DURING HIGH TIDE THROUGH SUNDAY.
ON SATURDAY, THE SAN FRANCISCO TIDAL GAUGE RECORDED 2.56 FT OF
INUNDATION. THE ALL TIME RECORD IS 2.98 FT FROM 1/27/1983. TODAY'S
HIGH TIDE WOULD RANK 4TH BEHIND FEBRUARY 6, 1998 WHEN THE GAUGE
REPORTED 2.67 FT ABOVE GROUND LEVEL. LOOKING AHEAD, HIGH TIDE IS
EXPECTED TO BE 1.9 FT ABOVE NORMAL AT 11:18 AM SUNDAY. THESE
PREDICTIONS INCLUDE UP TO 1 FOOT OF STORM SURGE THAT WILL ENHANCE
THE ASTRONOMICAL TIDE AND FLOODING THREAT. HIGH TIDE VARIES UP TO
90 MINUTES EARLIER OR LATER ALONG THE PACIFIC COAST AND THROUGH
THE SAN FRANCISCO BAY, RESPECTIVELY.
A BEACH HAZARD STATEMENT IS IN EFFECT SUNDAY. LARGE SWELL WILL
IMPACT THE PACIFIC BEACHES, GENERATING LARGE BREAKING WAVES UP TO
20 FEET, STRONG RIP CURRENTS, AND SNEAKER WAVES. INEXPERIENCED
SWIMMERS SHOULD AVOID THE WATER. NOBODY SHOULD CLIMB THE COASTAL
ROCKS. NEVER TURN YOUR BACK ON THE OCEAN.
MTR WATCHES/WARNINGS/ADVISORIES
CA...COASTAL FLOOD ADVISORY UNTIL 2 PM PST SUNDAY FOR CAZ006-505-506-
508-509-529-530.
BEACH HAZARDS STATEMENT FROM 6 AM PST SUNDAY THROUGH SUNDAY
EVENING FOR CAZ006-505-509-529-530.
PZ...SMALL CRAFT ADVISORY UNTIL 9 AM PST SUNDAY FOR MRY BAY.
SMALL CRAFT ADVISORY UNTIL 9 PM PST SUNDAY FOR PIGEON PT TO PT
PINOS 0-10 NM-PIGEON PT TO PT PINOS 10-60 NM-PT ARENA TO PT
REYES 0-10 NM-PT ARENA TO PT REYES 10-60 NM-PT PINOS TO PT
PIEDRAS BLANCAS 0-10 NM-PT REYES TO PIGEON PT 0-10 NM.
SHORT TERM...RGASS
LONG TERM....RGASS
AVIATION...MURDOCK
MARINE...MURDOCK
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