textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1200 PM PDT Sun Aug 2 2026

- Moderate HeatRisk in the interior through Monday with some patches lingering through the next week

- Near critical fire weather threat across the interior North and East Bays, and the Diablo and Santa Lucia ranges through Monday with elevated fire weather threat through the week

- Strong and gusty winds develop over coastal waters north of Point Reyes today, some offshore winds develop in the North Bay and SF Bay Area tonight through Monday morning

SHORT TERM

Issued at 1200 PM PDT Sun Aug 2 2026 (This evening through Monday night)

Another day, another Otter Eddy keeping the stratus in place over Monterey Bay and the immediately adjacent coastline. Clearing is expected through the next couple of hours with the stratus returning to the immediate coastal regions south of the Golden Gate and into the Salinas Valley tonight.

The high pressure system centered over the Desert Southwest and extending over California persists, with a trough deflected to the north around the Pacific Northwest and western Canada, and widespread temperatures above the seasonal averages continue today. Highs today range from the lower 90s to the triple digits in the inland valleys today, with warm spots in the far interior North Bay, the eastern part of Contra Costa County, and southern Monterey and San Benito Counties seeing highs up to 105 or 107. Elsewhere, highs along the bays range from the middle 70s to the middle 80s, while the Pacific coast hovers in the middle 60s to lower 70s. On Monday, morning lows range from the middle 50s to lower 60s in the lower elevations, to the middle 60s to the lower 70s in the higher elevations, and expect highs to be broadly similar to today's, with the most notable change being a couple degrees of cooling over southern Monterey County.

A rather strong north-south pressure gradient is resulting in gale- force wind gusts across the coastal waters, but the orientation of the winds remains generally parallel to the coast, so the strongest winds are not expected to migrate inland. Breezy and gusty winds are expected to develop in the afternoon and evening hours with gusts reaching 20 to 25 mph at the coast, through gaps and passes, and along the ridgelines. Tonight into Monday morning, some offshore winds are possible as the trough moves into the northern Rockies, bringing us a quasi-inside slider pattern overnight. The expected gusts of 15 to 20 mph aren't strong enough to issue a Wind Advisory, but they are contributing to near-critical fire weather concerns across the Bay Area, especially in the interior regions. See the FIRE WEATHER section for more details. One less spark, one less fire!

Widespread Moderate HeatRisk persists across the interior regions into Monday with patches of Moderate HeatRisk persisting into the rest of the week. This corresponds to a moderate risk for heat related illnesses for sensitive populations, including children, the elderly, pregnant women, people with certain medical conditions, and people who work or live outdoors without adequate shelter or hydration. Some patches of Major HeatRisk, corresponding to a more widespread risk for heat-related illnesses, are also expected in the warmest parts of the interior Central Coast. Follow these tips to avoid heat-related illnesses:

* Stay hydrated and drink plenty of fluids. * Wear lightweight, light-colored clothing. * Reduce time spent outdoors or stay in the shade. * Never leave people or pets unattended in vehicles. * Use sunscreen if going to the coast or the pool.

LONG TERM

Issued at 1200 PM PDT Sun Aug 2 2026 (Tuesday through next Saturday)

Subtle cooling is possible on Tuesday and Wednesday if onshore flow is able to rebuild as the high begins to redevelop. One of the big questions is how quickly the ridge can rebuild over California and the Great Basin in the wake of the trough's passage. The models are currently showing a slower rebuilding of the high pressure system heading into Wednesday, which corresponds to highs around the middle 80s to middle 90s in the inland valleys, but if the high builds faster than anticipated, these temperatures may need to be bumped up a few degrees.

In any case, the high pressure system should be redeveloped by the latter part of the week, causing temperatures to rise again. Heat Advisories may be necessary later this week into the upcoming weekend, assuming the current forecast trends continue.

AVIATION

(00Z TAFS) Issued at 448 PM PDT Sun Aug 2 2026

VFR is expected to prevail through the forecast period for most terminals except Monterey Bay and KHAF. The marine layer continues to struggle with building high pressure and will remain compressed back to the coastline. A weak local circulation in the wake of troughing to our north will result in another wave of weak offshore flow overnight into Monday morning, mainly across the North Bay and Bay Area.

Vicinity of SFO...VFR with a weak marine layer compressed back to the coast and another round of offshore overnight through Monday morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR until after midnight with IFR ceilings expected to develop late in the overnight and persist through at least mid-mofning Monday. When ceilings lift, VFR through the remainder of the forecast period.

MARINE

(Tonight through next Friday) Issued at 448 PM PDT Sun Aug 2 2026

Strong to near gale northwest winds continue on a downward trend to moderate breezes by Monday night. Frequent gale force gusts across the northern coastal waters also diminish to strong by Monday night. Rough to very rough NW seas around 10-15 feet follow in pursuit and subside to moderate by Tuesday night. Moderate seas around 4-8 feet prevail thereafter through Friday.

FIRE WEATHER

Issued at 1200 PM PDT Sun Aug 2 2026

Near critical fire weather conditions are expected through Monday and after a period of elevated fire weather conditions, potentially return later in the week. Temperatures remain around 10 to 15 degrees above normal across the interior through early next week with highs in the upper 80s to 90s. No major changes to the forecasted dry conditions. Daytime humidity retention remains poor across the interior (20-30%) with humidity values dropping into the 10s across the interior Central Coast, East Bay Hills/Valleys, and the higher elevations. Portions of the interior Central Coast may see daytime humidity values drop into the single digits through the next couple of days. Overnight RH recovery remains poor at locations above 2,000 feet with values between 25 to 40% expected with some favored locations struggling to reach even 25%. This will be particularly true across the Mayacamas, highest peaks of the East Bay Hills, the Diablo Range, the Santa Cruz Mountains, the Santa Lucia and Gabilan Ranges. Nocturnal drying (rapid decrease in RH through the pre- dawn hours) may also transpire which will increase the burn period or time in which fire behavior may remain active. Energy Release Component (ERC) values are projected to climb above the 97th percentile across the interior Central Coast, Mid Coast to Mendocino (North Bay), and Diablo- Santa Cruz (Diablo Mountains and Santa Cruz Mountains) zones within the next two days. Diurnally breezy onshore winds are expected along the coast, mountain gaps and passes, and along the ridgelines each afternoon/evening. In addition, a burst of offshore wind is forecast tonight into Monday morning for the SF Bay Area and the North Bay, increasing the risk for nocturnal drying events especially in downslope areas. With near critically dry conditions and above normal temperatures expected, individuals across these areas are advised to avoid activities that may spark a fire. Fire crews are urged to exercise extra caution when executing any prescribed burns, especially where fuels, topography, and weather align.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...Gale Warning until 9 PM PDT this evening for Pt Arena to Pt Reyes 0-10 nm.

Gale Warning until 3 AM PDT Monday for Pt Arena to Pt Reyes 10- 60 NM.

Small Craft Advisory until 3 PM PDT Monday for Pigeon Pt to Pt Pinos 10-60 NM.