textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1240 PM PDT Sat Aug 29 2026

- Another beautiful day Sunday

- Cooler weather this week

SHORT TERM

Issued at 1053 PM PDT Sat Aug 29 2026 (Tonight through Monday)

Saturday was a beautiful sunny day across the Bay Area and Central Coast and we'll get more of the same on Sunday. The marine layer stratus fully evaporated by noon as a much direr air mass moved in from the north. The 00Z weather balloon measured the precipitable water at 0.58", which is around the 10th percentile for this time of year. With unimpeded radiative cooling, marine layer stratus is starting to reform, with Half Moon Bay recording the first clouds overhead this evening. Coastal areas south of the Golden Gate will likely see the stratus come back before the sun rises Sunday morning. Inland valleys are more of a toss-up. The marine layer is currently 1,600' deep and will gradually expand over the next 24 hours. Any clouds that form will likely clear by midday with a mild, breezy, and clear afternoon.

Marine layer stratus should be much better organized by Monday morning. The depth will likely be around 2,000' by then, with less chance of clearing along the coast. As a short wave trough moves through, temperatures will also be around 5 degrees cooler than the weekend with a stronger onshore breeze in the afternoon.

LONG TERM

Issued at 1053 PM PDT Sat Aug 29 2026 (Monday night through next Saturday)

As the troughing pattern continues, the 850 mb temperature will bottom out around 6-10 C on Tuesday. That's about as low as it gets this time of year and more like a normal November day. High temperatures will be in the 60s and 70s with the typical marine layer stratus in the morning. The troughing pattern will deepen and a cut-off low will bring some early rain to the Pacific Northwest later this week. There is a chance for some light rain to make it as far south as the North Bay starting Tuesday. The ECMWF ensemble mean shows a few hundredths at Santa Rosa from Tuesday through Friday, with a 10% chance of reaching 1/2". The probability drops quickly further south outside of some marine layer drizzle along the coast. This cut-off low now looks like it will linger near Northern California into the weekend. If so, this low pressure breaks up the normal subtropical high and opens the door for tropical cyclones and the associated moisture to recurve to the north rather than being held in the tropical latitudes. While it's too early to say if that will happen, the persistent troughing pattern looks like it may keep the door open into next week.

AVIATION

(06Z TAFS) Issued at 918 PM PDT Sat Aug 29 2026

VFR prevails across the forecast area except for a newly developing patch of stratus /MVFR-IFR/ vicinity KHAF Airport and wildfire smoke reducing slant range and surface visibilities in southern Monterey County. A well established deep layered mid- latitude wind flow returned last night and today which thoroughly dried out the atmosphere at and above the lower level subsidence inversion (temperature inversion based at 1600 feet per latest 00z Oakland upper air sounding). Earlier today this drying combined with surface heating and fully mixed out even lingering coastal stratus and fog. Independent of the 500 mb pattern, thermal ridging remains between 925 mb and 700 mb tonight and Sunday. Model forecasts show stratus and fog returning tonight and Sunday morning, though it'll take time for redevelopment. A dry atmosphere above the lower level temperature inversion will result in radiative cooling tonight to daybreak Sunday. This and any near surface cool air advection and gentle upslope cooling will help coastal stratus and fog redevelopment. Most inland locations likely stay VFR tonight and Sunday.

Vicinity of SFO...VFR except tempo stratus /IFR/ 11z-15z Sunday. Stratus /IFR/ then returns early Monday morning. West wind 16 to 25 knots until 07z this evening, then west wind 10 knots tonight and Sunday morning. West wind 15 to 22 knots Sunday afternoon to mid evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. Radiative cooling combining with gentle upslope cooling will result in stratus and fog/mist /IFR- LIFR/ redevelopment tonight to daybreak Sunday. Tempo stratus and fog/mist /LIFR/ forecast 09z-14z, prevailing LIFR until late Sunday morning. Stratus, fog/mist mix out to VFR 17z Sunday. Stratus /IFR/ redevelops Sunday night. Winds mainly west to northwest 5 to 15 knots.

MARINE

(Tonight through next Friday) Issued at 909 PM PDT Sat Aug 29 2026

Fresh northwest breezes with strong to near gale force gusts steadily diminish to gentle by Monday. A long period southerly swell around 17 to 18 seconds persists into Sunday. Wind driven rough seas gradually subside back to moderate by the beginning of the work week.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...Small Craft Advisory until 3 AM PDT Sunday for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory until 9 PM PDT Sunday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.