textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1252 PM PDT Sun May 10 2026

- Warming and drying trend will continue through Monday

- Moderate risk for heat-related illnesses for sensitive populations across the interior on Monday

- Gradual cooling trend and unsettled weather midweek through late week

UPDATE

Issued at 845 PM PDT Sun May 10 2026

We're keeping an eye on the marine layer tonight as it continues blossom along the coast. It should deepen to about 1000ft tonight, which will bring low clouds into portions of the interior valleys. Guidance shows the clouds mixing out by mid to late morning, which may impact high temperatures tomorrow.

SHORT TERM

Issued at 1252 PM PDT Sun May 10 2026 (This evening through Monday)

Temperatures this afternoon are struggling to reach their forecasted highs. This is as a deeper marine layer around 1500 ft in the North Bay and 2000 ft in the Bay Area and Central Coast developed overnight. Again, where cloud cover lingers or is slow to dissipate across inland areas is where we are most likely to see cooler temperatures than previously forecasted. That said, inland clearing will still allow for temperatures to warm this afternoon as high pressure to the south of the region continues to strengthen.

Overnight, temperatures will cool into the upper 40s to mid 50s across most valley locations. Meanwhile, the higher ridges and peaks will likely bottom out in the upper 50s to 60s. If persistence holds, low clouds will fill back inland overnight, yet not expecting as much of an inland penetration as the marine layer is still on track to compress.

Monday is still on track to be the warmest day of the week, yet we are seeing less widespread Moderate HeatRisk across the interior. Mondays afternoon maximum temperatures are expected to be in the mid 80s to lower 90s across the interior with cooler conditions near the coast as a shallow marine layer and onshore flow will persist. However, these temperatures could be off by a few to several degrees where cloud cover develops and lingers. Tricky forecast as high pressure aloft supports warming afternoon temperatures, yet the marine influences have been winning out.

LONG TERM

Issued at 1252 PM PDT Sun May 10 2026 (Monday night through next Saturday)

The pattern begins to shift Monday night into Tuesday as a trough of low pressure approaches the Pacific Northwest and northern California. Thus, temperatures will cool by several degrees on Tuesday, yet are likely to remain above seasonal averages. A cut-off low pressure system is forecast to develop and move inland Tuesday night and into Wednesday bringing even cooler and unsettled weather to the region. We are still expecting drizzle and/or light rain Tuesday night through Thursday morning as a result of the mid/upper level cut-off low moving inland across northern California or the Bay Area. Rainfall amounts generally will remain less than a few hundredths of an inch or so.

More of a zonal flow returns by late week and will persist through the upcoming weekend. This will result in a warming and drying trend through this timeframe.

AVIATION

(06Z TAFS) Issued at 950 PM PDT Sun May 10 2026

No major changes to the forecast with this TAF package. Tonight's observations include Mainly VFR conditions with the exception being along the San Francisco Peninsula and Monterey coastlines where sites are reporting MVFR to IFR cigs. These will likely hold and even build for the overnight hours bringing MVFR to IFR ceilings. The marine layer is expected to be around 1000ft tonight which means the onset of stratus in the valleys will be delayed or non-existent. Most sites have hints of cigs, with them lifting by mid to late morning. VFR conditions are expected for the majority of the region by Monday afternoon. The marine layer looks to return again tomorrow evening, opted to hint or fully bring it in for terminals near the coast. Medium to high confidence in the forecast.

Vicinity of SFO...Westerly winds are winding down and will fall to around 10kt or less after 6Z. The challenge outside of winds is the stratus. Satellite imagery and webcams show stratus building around the San Francisco Peninsula and slowly filtering into the western portion of KSFO's range ring. With the marine layer expected to be around 1000ft again, we should see the return of stratus tonight. Kept the pessimism in the TAFs with IFR cigs based on the last few nights, but time will tell if go that low or stay in the MVFR category. Stratus looks to dissipate mid to late morning, with breezy westerlies of 10-15kt returning Monday afternoon. The marine layer looks to return Monday night into Tuesday morning, which was brought into the latest TAF. Medium confidence in the forecast.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...A small band of stratus remains around the Monterey Peninsula, which has been brought IFR cigs to KMRY. Expect this to build back in this evening bringing MVFR to IFR cigs to the terminals. Stratus should begin to erode by mid to late morning, though a few clouds could linger around KMRY for the afternoon. Stratus and low cigs look to return Monday evening.

MARINE

(Tonight through next Saturday) Issued at 845 PM PDT Sun May 10 2026

Moderate seas and a fresh to strong northwest breeze with isolated near gale force gusts continuing through tonight. Winds ease late tonight across the inner waters then across the outer waters tomorrow becoming a moderate to fresh northwest breeze. Seas subside in response, but remain moderate with 4 to 5 foot seas by mid week.Locally gusty conditions are likely across the San Pablo and San Francisco Bays where terrain promotes wind funneling. Winds increase and seas build again late Wednesday into Thursday.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt Reyes 0-10 nm.

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

Small Craft Advisory until 9 AM PDT Monday for Pigeon Pt to Pt Pinos 10-60 NM.