textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1259 PM PDT Wed Oct 7 2026

- Hot inland temperatures continue Thursday

- Sharp cool-down this weekend and early next week

- Coastal flooding during high tides and large swell this weekend

- Light rain possible early next week

SHORT TERM

Issued at 1155 PM PDT Wed Oct 7 2026 (Tonight through Sunday)

Strong 500 mb high pressure ridging bringing inland areas hot and dry weather will continue into Thursday. Well above early October normal temperatures occurred again today, though none of the long term stations set any new record highs today. The Heat Advisory (WMO header WWUS76) for inland areas continues through 10 pm PDT Thursday. And a reminder there is a Coastal Flood Advisory (WHUS36) for anomalous high tides with up to 1.2 feet of inundation above ground level in low-lying areas.

As mentioned it'll be hot again inland Thursday while cooler temperatures will prevail along the immediate coastline within a compressed marine layer. NBM forecast highs were nudged downward slightly for much of the immediate coastline for Thursday. Global models continue to indicate a major pattern shift will take place over the western states beginning later tomorrow through Friday. A weak 500 mb low ~ 900 miles to our west will progress toward our forecast area allowing part of the aforementioned 500 mb high pressure ridge to slip westward (retrogressing) far to our west. Separate strengthening 500 mb troughing will take place over the Pacific Northwest; long wave troughing will begin to replace long wave ridging over the west. Mid-latitude amplification and winds will move the 500 mb trough southward, decidedly shifting the pattern south and east including the near term weak 500 mb low just out ahead of it and the rest of the 500 mb ridge. This pattern shift will bring in much cooler air from the surface up through 500 mb across the forecast area through the weekend.

Winds will become gusty over the coastal waters and gap winds will increase as well during the weekend, both Saturday and perhaps Sunday with gusts possibly nearing wind advisory level in the usual wind favored gaps across the San Francisco Peninsula and the East Bay.

LONG TERM

Issued at 1155 PM PDT Wed Oct 7 2026 (Sunday night through next Wednesday)

Winds over land diminish later Sunday. There may be some residual moisture the cold core low will tap producing a few showers over the southern forecast area later Sunday and Monday. Otherwise dry and much cooler weather is forecast later Monday, Tuesday and Wednesday. Daytime highs and lows will shift to below normal. Daytime highs will generally be in the 60s coast to the 70s inland. Night-time and morning lows will mostly be in the 40s except around 50 at the coast and as cold as the 30s far inland valleys.

AVIATION

(06Z TAFS) Issued at 949 PM PDT Wed Oct 7 2026

Stratus is filling in along the coast with ceilings and visibilities dropping at HAF. The forecast remains more complicated for MRY and SNS where stratus is filling in much more slowly than originally anticipated within the Monterey Bay. The Monterey Buoy shows an air temperature of 59 degrees and a sea surface temperature of 65 degrees - indicating a good upwards transport of warm moist air and increasing likelihood of fog development. Thus, did not want to nix the mention of fog for MRY/SNS but did push it back by a few hours. Conditions are expected to improve by late morning but a deepening marine layer Thursday night into Friday should allow for an earlier stratus return along the coast (closer to 00Z than 06Z). Similar to last night, satellite shows some tendrils of stratus extending into the North Bay/San Francisco Bay areas but confidence is low that stratus will impact interior airports. Otherwise, moderate onshore winds continue during the afternoon and evening with lighter, variable to offshore winds continue overnight.

Vicinity of SFO...VFR. Satellite shows some low level stratus on the other side of the San Bruno Gap but confidence is low that it will reach the airport at this time. If stratus does reach SFO it is likely to be temporary in nature and not persist through the entire night. Breezy onshore winds expected during the afternoon and evening before winds weaken overnight.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...As mentioned above, stratus is slowly filtering into the Monterey Bay towards MRY and SNS. LIFR to IFR conditions are expected overnight as fog/low level stratus arrives. Confidence is slightly higher in fog development at MRY than SNS where most models have backed off of fog development tonight. Conditions look to improve by late morning before an early return of stratus tomorrow evening thanks to a deepening marine layer (approx. depth of 1000 ft). Moderate onshore winds continue during the day before winds weaken overnight.

MARINE

(Tonight through next Tuesday) Issued at 949 PM PDT Wed Oct 7 2026

A moderate to fresh northwesterly breeze and moderate seas continues through Thursday. A deep upper level trough will arrive Friday into the weekend and bring a return of strong to gale force northerly winds, rough to very rough seas, and wave heights between 10 to 15 feet. Conditions will be hazardous for small craft with small craft advisories to be issued for this event. The sea state will be very active as long period southerly swell and very long period westerly swell arrive this weekend into next week. Expect longer than normal lulls in between wave groups due to the long periods of the incoming swell groups.

FIRE WEATHER

Issued at 410 AM PDT Wed Oct 7 2026

Hot and dry conditions will lead to elevated fire weather conditions across the higher terrain through Thursday. Temperatures 10 to 20 degrees above normal and poor minimum relative humidity will continue away from the compressed marine layer at the coast. The higher terrain will experience active thermal belting, little-to-no recovery with nocturnal drying across the highest peaks, and thus prolonged burn periods. Winds remain the limiting factor, with diurnal winds prevailing except for light northerly/offshore flow overnight across the higher terrain. ERC values will rise to near records during the hot and dry conditions. A pattern change Friday into the weekend will bring cooler, moister, and windier conditions.

Sarment

MTR WATCHES/WARNINGS/ADVISORIES

CA...Coastal Flood Advisory from 9 AM Friday to 3 PM PDT Tuesday for CAZ006-508-529-530.

Heat Advisory until 10 PM PDT Thursday for CAZ503-504-506-508- 510-512>518.

Coastal Flood Advisory until 4 PM PDT Wednesday for CAZ506.

PZ...Small Craft Advisory from 3 AM to 3 PM PDT Friday for Pt Arena to Pt Reyes 10-60 NM.