FXUS66 KMTR 111744 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 944 AM PST Thu Dec 11 2025 ...New AVIATION... .KEY MESSAGES... Updated at 1110 PM PST Wed Dec 10 2025 - Hazardous beach conditions through Friday - Tule fog and stratus continue for the North and East Bay - Wetter pattern expected to begin next week && .UPDATE... Issued at 833 AM PST Thu Dec 11 2025 Very similar set up to this time yesterday as low clouds and/or fog persist over much the valley locations in the North Bay, East Bay, and South Bay. Seeing a bit more coverage across San Francisco and around the west side of the Bay Shoreline, however these conditions are expected to improve within the next few hours. Late afternoon clearing is also expected across much of the region, except across the far interior East Bay, southern portions of Napa and Sonoma County, and bay side areas of Marin County. Otherwise, the ongoing forecast remains on track at this time with no updates anticipated. RGass && .SHORT TERM... Issued at 1110 PM PST Wed Dec 10 2025 (Tonight through Friday) Different day, same weather. Tule fog continues to fill the Central Valley with spill over through the Delta and across the Valleys in the East Bay and North Bay. The visibility is already less than a mile at Livermore and Santa Rosa airports with a good chance to worsen through the night. As we've seen over the last several days, the fog and clouds should erode for most in the afternoon, but may linger along the Delta and San Pablo Bay regions. Anywhere in the fog will continue to deal with cold temperatures while those areas in full sunshine will quickly warm well above normal. The 00Z sounding found a surface temperature of 56 degrees while the temperature at 3,000 feet was 70 degrees. This strong inversion continues to make the max temperature forecast challenging with some areas up to 10 degrees cooler than normal and others up to 10 degrees warmer. We continue to rely heavily on the persistence forecast which has been performing better than any model recently. && .LONG TERM... Issued at 1110 PM PST Wed Dec 10 2025 (Friday night through next Wednesday) The forecast remains fairly consistent through Friday before the ridge axis finally slides to our East. This won't have a drastic effect immediately, but the temperatures should cool a couple degrees through the weekend. By Sunday or Monday we should start to see some high clouds, indicating that the ridge has flattened and zonal flow has moved in. This new pattern should help scour out the persistent fog. We also expect some light rain early next week, particularly across the North Bay. The most interesting development in the forecast is in the extended long range, where there is a moderate chance for an atmospheric river late next week. It's too early to talk about specific impacts or timing, but the Climate Predication Center has placed the Bay Area in a moderate risk for both heavy precipitation and strong winds from 12/18-12/21. The bullseye looks like far northern California, but that has been trending south over the last few model updates. && .AVIATION... (18Z TAFS) Issued at 937 AM PST Thu Dec 11 2025 Sounding like a broken record, but aviation impacts again this morning for N, E, and S Bay Terminals due to IFR conditions (cigs/fg). Similar to yesterday, patchy clouds were hit or miss inside SF Bay and that is the case again this morning. N and E Bay will be last to clear for KSTS,KAPC,KLVK. KSJC will be late morning for clearing. Monterey Bay terminals remains VFR. For tonight, will lean toward persistence, but as high pressure continues to build overhead the cloud deck will become more compressed leading to lower cigs and potential for more fog. overall conf is moderate. Vicinity of SFO...Feed south of the terminal drift north bringing IFR condition. Thankfully they'll be temporary. VFR expected this afternoon. No cigs in taf for tonight. SFO Bridge Approach...Similar to SFO. Slantwise vis could be reduced again this afternoon. Monterey Bay Terminals...VFR && .MARINE... (Today through Tuesday) Issued at 833 AM PST Thu Dec 11 2025 High pressure off of the coast will maintain northerly fresh breezes across the outer coastal waters with light to gentle breezes near shore. Light offshore winds will continue from the Delta to the San Francisco Bay and through the Golden Gate. A new, long period northwesterly swell will last into this weekend. && .BEACHES... Issued at 1110 PM PST Wed Dec 10 2025 Long period NW swell is causing hazardous beach conditions through Friday. This energy brings strong rip currents, an increased risk for sneaker waves, and large breaking waves. This coincides with nice warm weather, which will likely lure more people to the beach under a false sense of security. A Beach Hazard Statement is in effect through Friday evening. Respect the power of the ocean and never turn your back on it. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement through Friday evening for CAZ006-505- 509-529-530. PZ...Small Craft Advisory until 3 PM PST this afternoon for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...Flynn LONG TERM....Flynn AVIATION...RGass MARINE...RGass 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