Swell Matrix

Area Forecast Discussion

National Weather Service San Francisco CA

544 am PST Thu Dec 25 2025

Update

Issued at 532 AM PST Thu Dec 25 2025

The main rain band has passed to the east of us. Severe Thunderstorm Warnings and Flash Flood Warnings were issued overnight across the Bay Area as the damaging winds and intense rain came through the region. Wind gusts remain elevated across the region, and the immense rainfall is still making its way across the urban landscape of the Bay Area. We are continuing to receive reports of roadway flooding across the Bay Area. If you come across a flooded roadway, turn around, don't drown! Even if you don't, take care if you do have to travel across the region today, as the intense winds brought down trees, branches, and power lines across the roadways.

Scattered showers continue through the morning with the latest high resolution guidance showing a signal for some organized thunderstorms to return late this afternoon and this evening as a shortwave approaches the state.

Highest wind reports overnight are 92 mph at the North Peak Access Road PG&E station in northwestern San Mateo County, 91 mph at the O'Neill Sea Odyssey station near Santa Cruz harbor, and 90 mph at the Mount Umunhum PG&E station and the Gunsight Fire Road PG&E station in the Marin County highlands. Downtown San Francisco reported 0.74 inches of rain from 5 PM yesterday to 5 AM this morning.

DialH

Short Term

, Issued at 1052 PM PST Wed Dec 24 2025 (Tonight through Friday)

Don't let your guard down, the line of showers and thunderstorms with strong winds that swept through our area earlier this (Wednesday) evening was only a precursor to what is expected to be the most impactful line of storms yet, that is currently about to enter our outer marine zones about 100mi offshore. Impacts for the next line are expected to be felt by Midnight PST, with another round of strong wind, periods of heavy rain with the potential of low top supercells producing waterspouts that could move onshore as short-lived tornadoes or straight line winds up to 80 MPH or higher. The High Wind Warning remains in place until 10 AM PST Thursday (Christmas) morning and may be extended. Our Flood Watch remains in place until Friday night at 10 PM PST. The SPC continues to have our entire Pacific Coast line in a Marginal Risk for Severe Thunderstorms through early Friday morning at 4 AM. That means, the line off showers and thunderstorms progged to move onshore as early as late afternoon Thursday into the evening hours may be just as impactful as the one currently on our door step. That means all hazards mentioned above are in play through at least tomorrow night, along with the dangerous beach hazards and gale to near storm force winds over both our coastal and outer waters. If traveling Christmas day or night, expect extensive travel delays, along with power outages and urban/nuisance flooding.

Long Term

..issued at 1052 PM PST Wed Dec 24 2025 (Friday night through next Wednesday)

*Long term discussion remains unchanged from Wednesday afternoon update*

Starting in the early morning Friday, winds and shower activity will gradually decrease as the low pressure system offshore opens up into a trough and moves into northern Oregon. The associated surface trough axis will move across the Bay Area Friday evening. This will finally flip the winds back to northerly, bringing drier, cooler weather for the weekend. The 1000-500 mb thickness actually increases this weekend, with the cooling coming mainly from enhanced radiation during in the cloudless nights. Sunday through Tuesday look particularly calm, clear and cool as a 500 mb ridge sets in. The next troughing pattern looks probable on the 1st or 2nd, just in time for King Tides. There's no strong signal for major impacts yet, but the CW3E ECCC AR Activity tool shows higher than normal chances for atmospheric rivers through the first half of January.

Aviation

(12z TAFS) Issued at 347 AM PST Thu Dec 25 2025

The main band of intense rain and wind is making its way through the East Bay, South Bay, and the northern Monterey Bay region. It is expected to cointinue pushing eastwards through the next couple of hours. Behind the band, lighter rain prevails with winds remaining rather breezy, with a chance for showers continuing through the day. Mix of MVFR and VFR with mid-level clouds should prevail outside the convective activity, and the winds should continue to diminish through the TAF period.

Vicinity of SFO, Winds should continue to be rather gusty from a generally south to southeast direction through the TAF period, with MVFR to VFR with mid-level clouds prevailing. Gusts will top out around 35 kt through the morning, diminishing to 20 kt in the afternoon and evening hours. Chances for post-frontal convective showers continue through the TAF period.

SFO Bridge Approach, Similar to SFO.

Monterey Bay Terminals, Latest high resolution model output shows that the frontal line might not be as impactful in the Monterey Bay region compared towards the north. If it does hold through, the timeframe for impacts will be 13-15Z. Otherwise, generally southeast winds will continue through the rest of the TAF period with gusts up to 25 kt, scattered showers and generally MVFR to VFR with mid-level ceilings.

Marine

(today through Tuesday) Issued at 347 AM PST Thu Dec 25 2025

, HAZARDOUS MARINE CONDITIONS CONTINUE INTO EARLY FRIDAY, Southeast gales across the coastal waters continue through the pre-dawn hours of Friday morning. These dangerous winds are accompanied by a chance for thunderstorms and possible waterspouts through the early morning hours. Seas will rebuild to very rough from the choppy wind waves. These hazardous seas will linger through Friday, reinforced by a moderate westerly swell. If your vessel is not able to handle these conditions return to port or seek protected waters as soon as possible.

Beaches

Issued at 325 PM PST Wed Dec 24 2025

A Beach Hazards Statement has been issued for the coast through 4AM Friday. The main concerns include:blowing and drifting sand and wind waves up to 20 ft. The drifting sand and increased sea spray will also result in poor visibilities, affecting water rescues. Increased coastal erosion will be possible as well.

Watches, Warnings, Advisories

Ca, Beach Hazards Statement through late tonight for CAZ006-505-509- 529-530.

Flood Watch through Friday evening for CAZ006-502>506-508>510- 512>518-528>530.

High Wind Warning until 10 AM PST this morning for CAZ006-503- 505-509-517-528>530.

Wind Advisory until 10 AM PST this morning for CAZ502-504-506- 508-510-512>516-518.

PZ, Gale Warning until 3 AM PST Friday for Mry Bay-Pigeon Pt to Pt Pinos 10-60 NM-SF Bay N of Bay Bridge.

Storm Warning until 3 AM PST Friday for Pigeon Pt to Pt Pinos 0- 10 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.

Visit this site often? Consider supporting us with a $10 contribution.
Learn more