, Issued at 1201 PM PDT Fri Sep 11 2026 (This evening through Saturday night)
The return of the marine layer (around 1600 feet per 12Z OAK Upper Air Sounding) resulted in widespread coverage of stratus this morning, with the exception of the East Bay interior valleys. Since then, clouds are quickly retreating to the coast and are forecast to linger off of the Central Coast for much of the day. However, a weak frontal boundary approaching the North Bay is likely to bring a return of clear skies off of the North Bay coast this afternoon.
Despite mostly sunny sky conditions across the interior, today will be much cooler than previous days as the region remains in between mid/upper level cut-off low off of the British Columbia coast and high pressure confined to southern California, Nevada, and Arizona. Less confidence tonight in the amount of stratus that returns to the region as the aforementioned frontal boundary moves southward and then weakens.
The cut-off low will shift southward before moving into the Pacific Northwest Saturday night and into Sunday. As such, westerly to northwesterly winds will increase tomorrow afternoon and persist through Saturday night ahead of yet another frontal boundary. The strongest wind gusts will be between 25 to 35 mph with favored gaps, passes, and coastal regions gusts up to 45 mph. This cold front will sweep across the North Bay and Bay Area Saturday night into Sunday with no measurable precipitation forecast.
..issued at 1201 PM PDT Fri Sep 11 2026 (Sunday through next Thursday)
In wake of the frontal passage, offshore flow is forecast from Sunday night and into Monday night as 925 mb winds become northerly to northeasterly. However, the offshore flow is not forecast to be much greater than 20 kt (23 mph) at 925 mb, limiting fire weather concerns. Onshore winds are forecast to persist in the lower elevations with the strongest in the early afternoon and through the evening hours. Thus, the marine layer looks to hold around 1500 feet in depth through the weekend. As mentioned in the Fire Weather section of the AFD below, areas above the marine layer often experience nocturnal drying (during the overnight hours). That will be the case during this offshore event. The trough axis is forecast to move into the northern Rockies and the northern Plains early next week, diminishing the offshore wind potential.
Lingering troughiness along the West Coast will maintain cooler than average temperatures for much of next week. This will give way to temperatures warming into the 60s to lower 70s along the northwest facing coastal locations and low to upper 70s around the Santa Cruz region, bayshore, and coastal adjacent valleys. Meanwhile, interior valleys are forecast to reach into the upper 70s to mid 80s with the warmest interior valleys of the Central Coast reaching into the low 90s.
(00z TAFS) Issued at 416 PM PDT Fri Sep 11 2026
IFR-MVFR stratus lingers at the immediate coast, with satellite imagery revealing clearing skies associated with a weak frontal boundary lurking offshore. Will need to monitor the clearing as it pertains to stratus development this evening and overnight. As it is, the current forecast has a moderate confidence that the stratus moves inland this evening as the marine layer remains around 1000- 1500 feet. High resolution models are a little more optimistic in terms of keeping inland terminals VFR, but opted to maintain continuity with the previous forecast. Any stratus that forms will dissipate back to the immediate coast through the course of Saturday morning. Moderate onshore pattern winds with some strong gusts will continue through the evening hours, turning lighter overnight before resuming Saturday afternoon.
Vicinity of SFO, VFR through the day with moderate confidence that VFR conditions persist through the TAF period. Moderate northwest winds persist into the evening, with wind speeds slightly decreasing overnight before strong and gusty winds come to the terminal Saturday afternoon.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, VFR with moderate northwest winds through the evening, moderate confidence that LIFR ceilings develop overnight at the terminals as winds become light. Stratus retreats back to the immediate coast on Saturday morning with moderate northwest winds resuming in the afternoon.
(tonight through next Wednesday) Issued at 416 PM PDT Fri Sep 11 2026
Hazardous conditions for small craft will prevail late this weekend through mid next week. A moderate to fresh NW breeze will increase today into tomorrow to a strong breeze by early Sunday and continue into the early work week. Near gale force gusts to occasional gale force gusts are expected along the inner waters from Pigeon Point to Point Piedras Blancas, the Monterey Bay, and in portions of the San Francisco and San Pablo Bays. Moderate seas will build, becoming rough, by Monday in response to the stronger winds.
Ca, None. PZ, Small Craft Advisory from 9 AM to 9 PM PDT Saturday for Mry Bay- Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm- SF Bay N of Bay Bridge.
Small Craft Advisory until 9 PM PDT Saturday for Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 9 AM PDT Saturday for Pt Arena to Pt Reyes 10-60 NM.
