textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 303 AM PST Thu Nov 27 2025

- Dense Fog Advisory in effect until 10AM PST for the North Bay Interior Valleys and East Bay Interior Valleys

- Pleasant Thanksgiving Day area wide

- Cooler temperatures set in for Friday and the remainder of the extended forecast

SHORT TERM

Issued at 303 AM PST Thu Nov 27 2025 (Today and tonight)

Forecast remains on track for a very pleasant Thanksgiving Day across our area. Portions of the North Bay Interior Valleys and East Bay Interior Valleys (both have a Dense Fog Advisory in effect until 10am PST this morning) may have to wait until later this morning to start basking in the ample sunshine and light winds awaiting most of us for the afternoon and early evening. A weak disturbance to our north weakens H50 heights later today and overnight before amplified ridging is reestablished in the Pacific Northwest.

LONG TERM

Issued at 303 AM PST Thu Nov 27 2025 (Friday through Wednesday)

A relatively weak, dry cold front extending from the aforementioned disturbance tracking out of the Pacific Northwest into the Intermountain West by early Friday will cool our temperatures down to near seasonal averages into the weekend. By late Sunday, the Polar Jet amplifies further with little to no impacts on our ambient weather other than reinforcing the cooler temperatures through the remainder of the extended forecast. The pattern appears to be unsettled for the second half of next week, but consensus in the deterministic guidance that far out has been even more elusive recently than it normally is.

AVIATION

(12Z TAFS) Issued at 324 AM PST Thu Nov 27 2025

LIFR-VLIFR conditions have developed across the North and East Bay valleys with low confidence of further impacts to the main Bay Area terminals through the mid-morning hours. Stratus retreats to the Central Valley and adjacent areas in the far interior East Bay through the late morning hours. Light to moderate winds through the afternoon and evening with more onshore flow closer to the coast and continuing offshore winds inland. Low to moderate confidence of stratus returning to the Bay Area valleys tonight through Friday morning, highest in the North and East Bay valleys although some high resolution guidance also shows a stratus deck forming around SJC and migrating northwest towards SFO and OAK.

Vicinity of SFO... Moderate confidence VFR through the day with a possibility of LIFE stratus flowing in from the Delta through the morning. High cloud cover is making it difficult to gauge how close the stratus is to the terminal resulting in low confidence in timing of any potential stratus push, but not expecting the clouds to linger past 18Z. Moderate northwest winds develop in the afternoon before returning to a light flow overnight, with a low confidence (20-30% probability) that LIFR stratus impacts the terminal tonight through Friday morning.

SFO Bridge Approach... Confidence is slightly higher (30-40% probability) that stratus impacts the approach path, especially towards the southern end of the San Francisco Bay. Otherwise similar to SFO.

Monterey Bay Terminals... Moderate to high confidence for VFR through the TAF period, with high cloud cover obscuring any possible stratus layer over the southern Salinas Valley. Light to gentle drainage winds will turn moderately onshore in the afternoon and evening before resuming tonight. Some high resolution models are picking up on stratus potential Friday morning but this should fall after the end of the TAF period.

MARINE

(Today through Tuesday) Issued at 324 AM PST Thu Nov 27 2025

Dense fog has developed across the West Delta and may extend into the San Pablo Bay, expected to dissipate after sunrise. Moderate to fresh north winds are expected to develop today and Friday. Winds will decrease Saturday but pick up to a moderate to fresh north breeze on Sunday, with lighter winds expected for the early part of next week.

MTR WATCHES/WARNINGS/ADVISORIES

CA...Dense Fog Advisory until 10 AM PST this morning for CAZ506-510.

PZ...Dense Fog Advisory until 10 AM PST this morning for SF Bay N of Bay Bridge.

Small Craft Advisory from 9 AM to 9 PM PST Friday for Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory from 9 PM this evening to 9 PM PST Friday for Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory from 3 PM this afternoon to 9 AM PST Friday for Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory from 3 PM this afternoon to 9 PM PST Friday for Pigeon Pt to Pt Pinos 10-60 NM.