Issued at 654 AM PST Tue Nov 25 2025
Areas of to widespread dense fog continue to impact the region this morning especially in the North Bay valleys, East Bay valleys, southern Salinas Valley and around the Bay Shoreline where we now have a Dense Fog Advisory through 11 AM PST. Fog is also impacting the San Francisco Bay, San Pablo Bay, and the West Delta. Some fog is also being reported in San Jose with visibilities at SJC holding around 1/2 of a mile. Conditions are forecast to gradually improve beyond 11 AM, yet anyone driving should use low beam headlines and slow down to allow extra time to reach your destination when encountering dense fog. We will continue to monitor the foggy conditions closely throughout the morning.
RGass
, Issued at 252 AM PST Tue Nov 25 2025 (Today and tonight)
Primary concern in the short term is the dense fog that has developed overnight across the North Bay Interior Valleys and East Bay Interior Valleys, and may eventually have to be expanded further as we head toward and through sunrise. Attm a Dense Fog Advisory is in effect for the North Bay Interior Valleys and East Bay Interior Valleys until 11AM this morning.
An offshore surface high pressure under broader ridging aloft is pulling a weak fetch of offshore flow across much of our area today and tomorrow. Subsidence beneath the ridge should keep a shallow marine layer just offshore this afternoon and evening area wide, resulting in a nice day. Todays temperatures will be similar to yesterday for the North Bay and Bay Area, slightly warmer for inland areas over the Central Coast where morning fog won't be as extensive. Patchy dense fog is expected to develop once again later tonight into the overnight hours over the North Bay Interior Valleys, however coverage should decrease as drier air associated with the shifting ridge mixes closer to the surface.
..issued at 252 AM PST Tue Nov 25 2025 (Wednesday through Monday)
Gradual warming through the middle of the week remains on track with temperatures peaking on Thursday afternoon while a progressive trough to our north continues to quickly get deflected north and east of our area. Weak amplified ridging aloft over the Pacific Northwest on Friday won't stop a weak back door cold front from pushing south through our area during the day Friday, cooling most areas off by a few degrees. The forecast for the weekend and beyond lacks consensus, but cooler temperatures than what we'll see the next few days seems likely as the longwave synoptic pattern becomes highly amplified, allowing for cooler Canadian air to filter south across the entire West Coast.
(12z TAFS) Issued at 337 AM PST Tue Nov 25 2025
LIFR-VLIFR conditions have developed across the North Bay valleys, parts of the East Bay exposed to the influence of the Central Valley fog bank, and the southern reaches of the Salinas Valley. The Central Valley fog has taken advantage of drainage flows and has dropped into parts of the San Francisco Bay, where SFO is currently reporting an IFR ceiling although with good surface visibilities. Some further expansion of the stratus is possible, particularly as clear skies across the rest of the region promote radiational cooling effects. Light offshore flow will continue across the region through the day, promoting a continued feed from the Central Valley fog minus any solar heating and potentially delaying clearance times across the Bay Area. This, in turn, could continue to promote dense fog formation tonight into Wednesday, although the exact details are not certain at this time.
Vicinity of SFO, IFR conditions at best through the morning hours, with the southwest flow helping stave off the most severe impacts from the Central Valley fog bank. A more northerly flow developing through the morning could bring poor visibilities to the terminal. Stratus will take quite a while to clear out this morning with light winds expected through the day. There is the potential for stratus and low fog to develop tonight through Wednesday morning, which is not being captured very well by the high resolution models. Have kept the TAF above IFR for now, but pilots should keep track of TAF updates as the day evolves in case the chances for fog increase.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, Low to moderate confidence of VFR conditions through the TAF period. Clear skies and dry offshore flows can promote radiational cooling, but the winds also mix the lower layers and prevent stratus from forming through the morning. VFR conditions continues through the late afternoon with winds shifting to a light onshore flow.
(today through Sunday) Issued at 252 AM PST Tue Nov 25 2025
Dense fog has developed across the West Delta, into the San Pablo and San Francisco Bays, creating hazardous conditions for mariners through the morning hours. High pressure will persist over the coastal waters through mid to late week. Seas will gradually ease through the middle of the week with gentle to moderate northerly breezes. Winds will begin to increase again late week, building moderate to rough seas.
Issued at 923 PM PST Mon Nov 24 2025
The Beach Hazards Statement has been extended through 10 AM PST Tuesday. A long period northwesterly swell will result in an increased risk for sneaker waves and rip currents. Breaking waves of 13 to 18 feet are expected. Sneaker waves can unexpectedly run significantly farther up the beach than normal, including over rocks and jetties. Rip currents are typically more frequent and stronger in the vicinity of jetties, inlets, and piers.
Ca, Dense Fog Advisory until 11 AM PST this morning for CAZ006-506- 508-510-516.
Beach Hazards Statement until 10 AM PST this morning for CAZ006- 505-509-529-530.
PZ, Dense Fog Advisory until 11 AM PST this morning for SF Bay N of Bay Bridge.
