, Issued at 1200 PM PDT Tue May 12 2026 (This evening through Wednesday)
The satellite imagery shows stratus coverage across the coastal regions and some lingering into the valleys of the Bay Area as a thin layer of high clouds persists over the region, with gradual clearing across the inland and Bayshore regions into the afternoon while the coast remains socked in. Stratus coverage should rebuild this evening and overnight but should not come as far into the southern Salinas Valley or the North Bay valleys as we saw this morning.
The large scale weather pattern features a departing ridge moving into the northern and central Rockies while a trough centered on an upper level low around 500 miles to the west of the Oregon Coast moves in, resulting in a gradual cooling trend today into Wednesday and an expansion of the marine layer. The latest readings from the Bodega Bay profiler suggest a marine layer around 1500-2000 feet thick, remaining rather consistent through the next couple of days as the trough passes through the region. High temperatures today will range from the upper 70s to the lower 80s in the inland valleys, the upper 80s to lower 90s in southern Monterey and San Benito Counties, the middle 60s to the middle 70s in the bayshore regions, and the upper 50s to lower 60s along the Pacific coast. Highs might be a few degrees cooler where the stratus is slower to dissipate than the forecast or does not clear out this afternoon. Low temperatures on Wednesday morning range from the upper 40s to the middle 50s across the lower elevations, while Wednesday's highs will range from the lower 70s to the lower 80s for the inland valleys.
As the trough moves through, the increasing pressure gradients will result in breezy and gusty winds starting this afternoon through Wednesday, with the gusts reaching 20 to 30 mph across the coastal and higher elevation regions and the northern Salinas Valley. Isolated favored regions, namely the Mayacama range and the Altamont Pass, may reach gusts of 40 to 45 mph this evening and overnight.
Elevated fire weather risks will set up starting this afternoon across a narrow strip of the far interior San Benito and Monterey counties adjacent to the Central Valley. A particularly concerning combination of gusty winds, hot temperatures, low daytime humidities, and poor overnight humidity recoveries across this region will result in a period of elevated fire weather concerns across this strip through the evening hours. Any fires that start in the drier grasses across this region may take hold and spread rather quickly. Our neighbors in Hanford have issued a Red Flag Warning for the adjacent zones across the western edge of Fresno County, but in our area of responsibility. the fire weather concerns are not widespread enough to warrant any products.
..issued at 1200 PM PDT Tue May 12 2026 (Wednesday night through next Monday)
As the trough moves out, warmer and drier weather will return to the region with highs on Thursday and Friday in the 80s to the lower 90s in the interior valleys, the middle 70s to lower 80s across the Bays, and the lower to middle 60s in the Pacific coast. A second trough coming down from the Gulf of Alaska will interrupt the warming trend this weekend, with inland highs dipping in to the lower 70s to lower 80s on Saturday before bouncing back to the upper 70s to middle 80s for Sunday.
Uncertainty in the forecast starts to increase in the early part of next week as the ensemble models struggle to diagnose the interaction between an upper level ridge and trough over the western United States. Model ensemble means from the American GEFS, European ECMWF, and Canadian GEPS models suggest a ridge over the eastern Pacific and a trough over the Rockies should develop by Monday morning, although with significant differences in the strength of both features. However, a peek into the model ensemble clusters reveals a significant minority of the ensemble members (around 30- 40%) show an alternate scenario where more zonal flow or troughing develops over the West Coast, nudging the forecast towards cooler temperatures. Past the 7-day outlook, CPC outlooks into the later part of May show a slight lean towards temperatures above seasonal averages, and precipitation totals near or above seasonal averages.
(18z TAFS) Issued at 1059 AM PDT Tue May 12 2026
A deep marine layer produced widespread stratus across the region this morning. Stratus is receding with all sites except HAF and MRY likely to clear by 19/20Z. Winds strengthen by the afternoon/evening with gusts to around 20-30 knots expected along the coastline. A dry cold front will push through tonight with moderate confidence in the timing of cloud cover arrival. Currently kept a later stratus arrival (09/10Z) for most sites but LAMP guidance shows some potential for stratus to return closer to 05/06Z. This cold front will also result in widespread gusty winds along the coast and across the bay shoreline early tomorrow morning. For now, kept tomorrow morning's gusts limited to HAF, OAK, and SFO but gusts are expected to pick up at the remaining airports after 18Z tomorrow.
Vicinity of SFO, Stratus is receding from SFO and should dissipate by 19Z. Gusts are expected to pick up by late this morning with the site to remain gusty through the end of the TAF period. Bumped up the afternoon/evening gusts to 30 knots with around a 10% chance of stronger gusts to 35 knots. We do expect gusts to ease slightly overnight (20-25 knots) but gustier winds (30-35 knots) are expected to return tomorrow afternoon/evening. Moderate confidence that stratus will return around 09Z with some potential for stratus to return as early as 03-06Z. Stratus should clear by late tomorrow morning with VFR conditions through the end of the TAF period.
SFO Bridge Approach. Generally similar to SFO. Expect stratus to fill in over the bay this evening and linger through late tomorrow morning. Similar to SFO, gusty winds are expected over the bay with the potential for sustained winds around 20 knots and gusts between 30-35 knots tomorrow afternoon/evening.
Monterey Bay Terminals, VFR at SNS through early this evening. IFR- LIFR CIGs are expected to persist at MRY through the TAF period with a continued stream of stratus onshore making it unlikely for MRY to clear this afternoon. Moderate confidence in IFR-LIFR CIGs developing again tonight with LIFR CIGs becoming more likely by early tomorrow morning. Breezy onshore winds are expected this afternoon/evening with gustier onshore winds to develop late tomorrow morning and continuing through the evening.
(tonight through next Sunday) Issued at 949 PM PDT Mon May 11 2026
Occasional strong gusts continue through tonight across the far northern outer waters. Otherwise, a moderate to fresh northwest breeze will continue over the waters through midweek. Seas subside but remain moderate with 4 to 6 foot seas through midweek. Winds increase and seas build starting mid-week with gale force winds and wave heights in excess of 10 feet likely starting Friday and continuing through the weekend.
Ca, None. PZ, Small Craft Advisory from 9 AM to 9 PM PDT Wednesday for Mry Bay.
Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Thursday for Pt Arena to Pt Reyes 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 9 AM Wednesday to 3 AM PDT Thursday for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10- 60 NM-Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory from 3 AM Wednesday to 3 AM PDT Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
