, Issued at 1243 AM PST Wed Mar 4 2026 (Today and tonight)
A cold front will move through today. The leading edge of high clouds associated with the upper level trough have reached the Bay Area but will quickly clear out through the late morning. The big question is if this front will bring any rain. The current air mass is pretty dry. The 00Z sounding measured a PW of 0.47", which is below normal for this time of year. The new air mass behind the cold front drier still, with PW eventually dropping below 0.4" this evening. However, there is a narrow band of low level moisture associated with FROPA this morning that may be enough to trigger some light rain or drizzle, particularly where enhanced by terrain. While there is no chance for any notable accumulation, I do expect windshield wipers to be called into service for the morning commute. The cold front is fairly progressive, it will move through the Golden Gate around 9 AM and clear Big Sur by noon. The clouds will clear quickly after the front passes. The biggest weather impact today will be strong NW winds behind the front. These winds are driven by the gradient between strong high pressure in the Eastern Pacific and the surface low associated with the cold front (roughly 1037 mb vs 1008 mb). Expect sustained NW winds of 10-15 mph with gusts to 25 mph through the afternoon and early evening hours. Winds will be at least 10 mph stronger along portions of the coast exposed to NW winds.
..issued at 1243 AM PST Wed Mar 4 2026 (Thursday through Tuesday)
The strong winds will continue through Friday or Saturday, although the direction will gradually veer from W today, NW Thursday, N Friday, and NE Saturday. This wind shift is in response to an evolving 500 mb pattern where the short wave trough moves through today, digs deeper over the Rockies Thursday, and eventually spawns a cut-off low by Saturday that moves off the coast of NW Mexico while a ridge builds over the CA/OR border. This is the classic "inside slider" pattern that brings surface high pressure over the Great Basin and low pressure to the subtropical Eastern Pacific. The SFO-WMC gradient will peak around +8 mb (onshore) today before plummeting to around -8 mb (offshore) by Saturday. This evolution will trigger down- gradient N or NE winds to California. These offshore winds, combined with the dry post-frontal air mass, will bring warm temperatures and low dew points through the weekend and into early next week. Afternoon temperatures will easily reach the 70s this weekend (including along the coast), while the dry air and clear skies will allow morning temperatures to drop into the 40s. The inside slider pattern will likely break down by the middle of next week as more zonal flow returns. While we may get some clouds to return, there is no significant rain expected through the middle of the month.
(12z TAFS) Issued at 338 AM PST Wed Mar 4 2026
A dry cold front is moving through the Bay Area this morning. This front is bringing a layer of high clouds above the stratus, but very little if any precipitation. The clouds will quickly clear through the late morning a few hours after the front passes. The biggest impact will be strong NW winds behind the front through the afternoon and early evening hours.
Vicinity of SFO, Broken MVFR ceilings are expected through 18-20Z or so. There may be some brief improvement in the early morning, but the more widespread VFR conditions will come after the front moves through late this morning. Winds will gradually ramp up through the day, with the strongest winds expected between 23Z and 01Z. Frequent gusts to 35 knots are expected during this window.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, A mix of IFR and MVFR conditions will continue through around 20-22Z when post-frontal clearing will take over. Strong NW winds will move in behind the front, with gusts to 25 knots expected.
(today through Monday) Issued at 338 AM PST Wed Mar 4 2026
A fresh NW breeze will increase to a strong NNW breeze tonight and reach near gale force on Thursday. These winds will build very rough seas of 12 to 15 feet across exposed waters Thursday through Friday. Conditions will gradually improve through the weekend as winds decrease and seas subside.
Ca, None. PZ, Small Craft Advisory from noon today to 3 AM PST Thursday for SF Bay N of Bay Bridge.
Small Craft Advisory from noon today to 9 PM PST Thursday for Mry Bay.
Small Craft Advisory until 9 AM PST Friday for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory until 9 PM PST this evening for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Reyes to Pigeon Pt 0-10 nm.
Gale Warning from 9 PM this evening to 9 AM PST Thursday for Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory until 3 PM PST this afternoon for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Gale Warning from 3 PM this afternoon to 9 AM PST Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 AM PST Thursday for Pt Arena to Pt Reyes 10-60 NM.
Gale Warning from 9 AM Thursday to 9 AM PST Friday for Pt Arena to Pt Reyes 10-60 NM.
Gale Warning from 9 PM this evening to 3 AM PST Friday for Pigeon Pt to Pt Pinos 10-60 NM.
