Swell Matrix

Area Forecast Discussion

National Weather Service San Francisco CA

431 pm PST Wed Mar 4 2026

Short Term

, Issued at 1204 PM PST Wed Mar 4 2026 (This evening through Thursday)

A dry cold front associated with a low pressure system moving into the Pacific Northwest is moving through the Bay Area, with some lingering low level clouds across the Bay Area that should dissipate through the early afternoon hours. The main forecast issue is the breezy winds that will develop through the day today and last for the next couple of days, as the low pressure system moves inland and turns to the southeast into the Great Basin, strengthening the pressure gradient and promoting stronger winds across the region. Northwesterly wind gusts today will top out around 20 to 30 mph across the valleys, and reach 35 to 45 mph in exposed coastal areas and the higher elevations. Overnight, winds will abate in the valley regions, but remain breezy and gusty in the coastal and higher terrain areas, where wind gusts remain in the 30 to 40 mph range as the wind turns to come from the north. This should promote low level mixing overnight and thus help to disrupt stratus formation that would otherwise occur. On Thursday, the wind gusts will resume from the north in the valleys, with gust speeds around the same as those seen today.

High temperatures for the next couple of days across the region range from the lower to middle 60s in the lower elevations, with patches of warm spots in the upper 60s, to the upper 40s and 50s across the higher elevations. Low temperatures hover in the upper 30s to lower 40s away from the immediate coast, where low temperatures in the upper 40s to lower 50s persist.

Long Term

..issued at 1204 PM PST Wed Mar 4 2026 (Thursday night through next Tuesday)

Breezy and gusty winds will continue through Friday and Saturday as a branch of the low pressure system retrogrades from the Great Basin into the Desert Southwest, before emerging as a cut-off low that traverses the northern end of Baja California and pauses just off the coast. The interaction between this low and high pressure from the eastern Pacific building into the Great Basin will result in an inside slider pattern that will continue veering the winds to a northeast flow late on Friday into Saturday. For context, as of the last available report at 8 AM today, the SFO-WMC gradient was +7.6 mb (an onshore pressure gradient). The PG&E WRF ensemble model is showing this reversing to around -8 mb (offshore) by the latter part of Friday into Saturday, with the European and American global ensemble models showing a slightly stronger offshore gradient at around -10 mb at the same time. Thus, a warming and drying pattern is expected where high temperatures rise into the lower to middle 70s for the valley regions, and even patches along the coast, for the upcoming weekend.

As the eastern Pacific high starts to diminish and the cut-off low moves eastwards again, the gradients will relax beginning on Sunday and will result in calmer winds heading into the early part of next week. Clouds may return to the region as the upper level flow shifts to a more zonal pattern, but temperatures remain seasonably warm and no rain is in sight for the foreseeable future, including beyond the 7-day forecast as CPC outlooks suggest that temperatures above seasonal averages and precipitation totals below seasonal averages are likely towards the middle of March and ensemble model means show a strong signal for ridging across the western United States around this time.

Aviation

(00z TAFS) Issued at 431 PM PST Wed Mar 4 2026

Post cold frontal drying continues across the forecast area supporting VFR through the evening, overnight and Thursday. Satellite at the moment shows a few areas of low clouds over the higher coastal terrain otherwise it's mainly clear to clear. Gusty west to northwest winds will continue into the evening with some surface wind decoupling in the valleys tonight and Thursday morning. Breezy to gusty northwest to north winds are forecast for Thursday.

Vicinity of SFO, VFR. West wind gusts to 35 knots through 05z then only a gradually decreasing west wind tonight and Thursday morning. West to northwest wind 15 to 25 knots Thursday afternoon and evening.

SFO Bridge Approach, Similar to SFO.

Monterey Bay Terminals, VFR. West to northwest wind gusts to 25 knots through early to mid evening then decreasing tonight and Thursday morning. West to northwest wind 15 to 25 knots Thursday afternoon.

Marine

(tonight through next Tuesday) Issued at 415 PM PST Wed Mar 4 2026

A strong NNW breeze this evening with gale fore gusts continuing into 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 diminish and seas subside.

Watches, Warnings, Advisories

Ca, None. PZ, Small Craft Advisory until 3 AM PST Thursday for SF Bay N of Bay Bridge.

Small Craft Advisory until 9 PM PST Thursday for Mry Bay.

Small Craft Advisory until 9 AM PST Friday for Pt Arena to Pt Reyes 0-10 nm.

Gale Warning until 9 AM PST Thursday for Pigeon Pt to Pt Pinos 0- 10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 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 until 3 AM PST Friday for Pigeon Pt to Pt Pinos 10- 60 NM.

Visit this site often? Consider supporting us with a $10 contribution.
Learn more