textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1227 AM PDT Wed Oct 28 2026

- Moderate coastal flooding at high tide for Bayshore and Pacific Coast locations through the week

- Seasonal to slightly below seasonal temperatures through the extended forecast

- Potential for rain this weekend and again early to mid next week

SHORT TERM

Issued at 142 PM PDT Wed Oct 28 2026 (This evening through Thursday night)

The sun is out across the Bay Area and Central Coast this afternoon, but you would not know it by looking at the temperatures. Seasonably cool conditions prevail across the region thanks to a relatively cool airmass overhead (850mb temps below normal). Despite the cooler than normal temps, it's still a pleasant afternoon with temps mainly in the 60s and a few 70s across the far interior.

This evening through Thursday night - Longwave pattern overview shows much of the West Coast under the influence of broad upper trough and a robust upper low anchored over the PacNW. Flowing into the upper trough is a decaying, weaker upper low due west of the Bay Area. This feature is helping to spread some high level clouds over the Central Coast this afternoon. Expect clouds to increase over the region tonight. The cloud cover will lead to slightly warmer overnight lows compare to this morning. For Thursday, still seasonably cool with similar afternoon temperatures. The PacNW upper low slow drifts southward through the day. As this happens, the decaying upper low interacts with an embedded shortwave trough rounding the base of the broad upper trough. As such, a few CAMs develop modeled radar reflectivity over the Bay Area tomorrow. Resolved QPF is showing zero. As such, forecast will reamin dry for now, but it's possible for KMUX radar to show a few echoes tomorrow afternoon (probably virga at best).

LONG TERM

Issued at 240 PM PDT Wed Oct 28 2026 (Friday through next Tuesday)

To round out the work week the southward drift of the upper low continues with further deepening of the broad upper trough. Temperatures cool a few degrees in response to the deepening trough and onshore flow.

Now for the big question in the long term: will it rain and will it impact Halloween? The answer is yes, but not a lot and not everywhere. Early on Saturday the deepening trough will get a boost from a cyclonically enhance jet max moving in SoCal/Central Coast. This will help to facilitate cyclogenesis. The developing offshore sfc low will then take aim at SoCal. The northern fringe of this system will have the greatest chance for impacts to the Central Coast leaving the heart of the Bay Area less likely for precip Saturday afternoon into Sunday. The forecast as of now brings some light rain to the Central Coast Saturday afternoon and then spreading chances slightly northward by Saturday evening with rain chances ending by early Sunday. Basically Hollister/Santa Cruz northward will be little (a few showers) to no precip and areas southward a few hundredths to three tenths of an inch. Simply put, Bay Area doen't be surprised so see a few drops if you have outdoor activities planned for Halloween. Monterey Bay region and southward don't be surprised to see light rain or a few showers.

Dry weather briefly returns Sunday into Monday with a slight warm up due to ridging.

Tuesday and beyond are lower confidence forecast as the EPac remains active, but details vary depending upon model of choice. Given the uncertainty, we do have a few chances for precip, but nothing noteworthy at this time. A few weak systems nose their way into a ridge.

Coastal flooding concerns continue across Bayshore locations within the San Pablo, San Francisco, and Monterey Bays through Saturday and the Pacific coastal regions through Friday. At the San Francisco tidal gauge, high tide is expected to be 1.9 ft above normal (7.7 ft MLLW) at 01:43 PM Thursday 10/29, 1.6 ft above normal (7.4 ft MLLW) at 02:39 PM Friday 10/30, and 1.1 feet above normal (6.9 ft MLLW) at 03:44 PM on Saturday 10/31, including around 1.2 ft of surge residual partially attributed to impacts from El Nino.

AVIATION

(00Z TAFS) Issued at 416 PM PDT Wed Oct 28 2026

Afternoon and early evening onshore winds will become light and variable then light offshore tonight and Thursday morning. Surface high pressure over far northern California and the Great Basin will weaken by later Thursday. High and mid level clouds will gradually increase tonight and Thursday, reducing radiative cooling tonight and radiative warming Thursday. VFR is forecast in the 00z TAFs.

Vicinity of SFO...VFR. West wind 10 to 12 knots decreasing to light west to northwest wind then shifting to light northeast Thursday morning. West to northwest wind 10 knots Thursday afternoon and early evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. West to northwest winds near 10 knots becoming light and variable then light east to southeast tonight and Thursday morning. West to northwest winds near 10 knots Thursday afternoon and early evening.

MARINE

(Tonight through next Monday) Issued at 408 PM PDT Wed Oct 28 2026

Moderate to strong northwest winds continue into the night across the outer waters with fresh to moderate breezes along coastal waters, with seas continuing to build in response and resulting in rough seas over exposed waters. Expect gradually improving conditions by Thursday and into the early part of the weekend. A long period west-northwest swell is forecast to arrive late this weekend and into early next week.

MTR WATCHES/WARNINGS/ADVISORIES

CA...Coastal Flood Advisory until 6 PM PDT Saturday for CAZ006-506- 508-529-530.

Coastal Flood Advisory until 5 PM PDT Friday for CAZ505-509.

PZ...Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory until 9 PM PDT Thursday for Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory until 3 PM PDT Thursday for Pigeon Pt to Pt Pinos 10-60 NM.