, Issued at 1204 PM PDT Sat Sep 26 2026 (This evening through Sunday night)
The stratus deck has mixed out to the immediate coast of Marin County and the Ocean Beach side of San Francisco and lurking near or just off the coast of San Mateo County. High clouds continue to flow over the North Bay and will continue to do so through the day, as the stratus deck returns to many of the coastal valleys this evening into the overnight period.
A developing trough with an axis around 600 miles west of Cape Mendocino is approaching the West Coast, digging deeper into the upper level flow as it does so and eventually dropping deep enough to cross into the California coast, where it should further develop into a cut-off low somewhere around the North Coast and the northern half of the Central Valley through the latter portion of Sunday. The influence of the cut-off low will bring cooler and more moist conditions to the region. High temperatures will range around 5 to 15 degrees below seasonal averages for today and Sunday, with highs in the inland valleys reaching the middle 70s to lower 80s today and the 70s on Sunday. High temperatures in the warmest portions of southern Monterey County will range from the middle 80s to lower 90s today, and the upper 70s to middle 80s on Sunday. Meanwhile, the Bayshore regions should expect highs in the upper 60s to upper 70s on Saturday and the middle 60s to middle 70s on Sunday, while the Pacific coast remains relatively cool with highs in the upper 50s to middle 60s on both days.
As the cut-off low moves across the state through the weekend, cooler temperatures and some incoming moisture should result in a wetter mid-layer, around the 300-500 mb layer. Exceedingly dry lower layers should cause the evaporation of most precipitation that may result, but can't rule out a few sprinkles overnight for the coastal regions and the highest peaks.
..issued at 1204 PM PDT Sat Sep 26 2026 (Monday through next Friday)
Ridging should return to the region on Monday as the low moves into the Mojave Desert, setting up pushes of higher elevation offshore flow each morning from Monday to Wednesday, chiefly across the North and East Bay interior mountains. The strongest push looks to be on Tuesday morning with wind gusts of 25 to 35 mph possible in the interior mountains of the North Bay. The potential for wind gusts above 35 mph is greatest at the ridgeline of the Vaca Mountains along the eastern border of Napa County.
Otherwise, the arrival of the ridge should allow for temperatures to warm for the next week. By Tuesday, highs should reach the middle 80s to middle 90s in the inland valleys, the middle 70s to the middle 80s for the Bayshore regions, and the 60s to the lower 70s for the Pacific coast. These highs should basically remain stable through the rest of the 7-day outlook as ensemble model means and cluster guidance suggest that the ridging pattern should stick around in some shape or form into the upcoming weekend and possibly beyond.
(00z TAFS) Issued at 429 PM PDT Sat Sep 26 2026
VFR across the board this afternoon. Similar to last night and earlier this morning, there is uncertainty in the timing and extent of stratus development tonight into Sunday. The KOAK 00z sounding measured a relatively weak marine layer up to approximately 1000ft. MVFR/IFR ceilings are possible after midnight for the Bay Area terminals and around sunset tonight for the Monterey Bay area sites.
Vicinity of SFO, VFR through the remainder of this afternoon and evening with a chance of MVFR/IFR ceilings developing late in the overnight period to near sunrise with clearing to VFR expected by mid-morning Sunday. Breezy onshore flow is expected by Sunday afternoon.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, MVFR/IFR ceilings are expected to develop after sunset and persist through mid-morning Sunday with VFR thereafter and relatively light winds Sunday afternoon.
(tonight through next Thursday) Issued at 429 PM PDT Sat Sep 26 2026
Moderate north winds will persist through the remainder of the weekend. Winds will increase Sunday night into Monday becoming strong and gusty as a ridge of high pressure begins building in over the EPAC tightening the pressure gradient across the coastal waters. Strongest winds will be over the outer coastal waters accompanies resulting in hazardous boating conditions.
Ca, None. PZ, Small Craft Advisory until 3 AM PDT Monday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 AM PDT Monday for Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 10-60 NM.
