textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 155 AM PDT Tue Oct 6 2026

- Hazardous heat inland persist through Thursday, never leave children or pets in unattended vehicles!

- Elevated fire weather conditions persist in the interior through Thursday

- Coastal flooding concerns due to astronomical tides and thermal expansion through the weekend - Hazardous beach conditions along Pacific coastline later this week into the weekend due to long period swell

SHORT TERM

Issued at 155 AM PDT Tue Oct 6 2026 (Today and tonight)

A shallow and compressed marine layer confined to the coast most of Monday afternoon has made some slight progress inland over the Russian River Valley, city of San Francisco and Monterey Bay into the Salinas Valley into the overnight hours. The low ceilings/patchy fog may limit visibility down to 1/2mi or less overnight into early Tuesday morning. The ridging pattern over our area will continue to be reinforced today and tonight in the wake of the weak disturbance that shifted east yesterday. Moderate HeatRisk continues to be the primary concern in the short term forecast along with elevated fire weather conditions, especially for higher elevation locations due to hot and dry conditions.

Follow these tips to avoid heat exhaustion and heatstroke:

* 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 155 AM PDT Tue Oct 6 2026 (Wednesday through Monday)

Wednesday and Thursday will see similar temperatures as today, however improved onshore flow developing during the day on Thursday will mark the beginning of a return to more normal or slightly below normal temperatures for Friday into the weekend. Another weak upper level disturbance will develop offshore similar to this past weekend, however its fate appears to be a merger with the remnants of Rachel. While Rachel and that disturbance merge, a more potent trough embedded in the Polar Jet will lift Rachel's remnants into the desert southwest while providing us with a potential 'inside slider'. Whether the energy associated with the Polar Jet increases onshore flow (deterministic GFS) or an inside slider (deterministic ECMWF), we're going to see dry and gusty winds develop over the weekend potentially increasing fire weather concerns, with the inside slider scenario possibly leading to another warm- up. The gusty winds over the East Bay may approach wind advisory levels Saturday morning albeit at high elevations. Unfortunately we continue to be dry through the extended forecast.

AVIATION

(06Z TAFS) Issued at 947 PM PDT Mon Oct 5 2026

Stratus has settled in along the coastline and is trying to intrude into the North Bay/Golden Gate Gap areas. Confidence remains low that stratus will reach STS, SFO, or OAK but there remains a slight chance. Night shift will need to keep an eye as to if the Golden Gate Gap stratus intrusion is able to hold together and if it starts to push towards SFO/OAK. Model guidance is underdoing the amount of stratus along our coastline with HAF and MRY reporting LIFR conditions as of 4Z. Fog will set in along the coast overnight and impact HAF, MRY, and SNS. If stratus is able to reach STS, OAK, or SFO it is likely that temporary reductions in visibility/ceiling height to IFR-LIFR conditions will occur. Conditions improve mid to late morning with model guidance mixed as to when stratus will return tomorrow night. Satellite shows a swath of dry air pushing north to south towards our coastal waters which may impact our stratus chances for tomorrow night. Winds remain diurnally breezy with moderate onshore winds during the day and lighter, variable winds overnight.

Vicinity of SFO...VFR with a low potential for IFR-LIFR conditions overnight if the shallow marine layer/stratus deck is able to make it into the San Francisco Bay. Confidence remains low that stratus will make it to SFO but chances increase slightly (10-20%) between 12 to 18Z. Moderate onshore winds expected during the day with winds decreasing overnight.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...LIFR conditions expected with fog to develop tonight. Visibilities drop to 1/2SM with the potential for dense (1/4SM) fog to develop. Moderate confidence that conditions will improve by 18Z but significant improvement may occur as late as 20Z. The caveat is the drier airmass moving in offshore, visible on satellite imagery, which may result in stratus/fog clearing slightly earlier than expected if the drier air makes it closer to shore. Light onshore winds continue at MRY through the day while moderate onshore winds return to SNS.

MARINE

(Tonight through next Sunday) Issued at 947 PM PDT Mon Oct 5 2026

A gentle to moderate northwesterly breeze continues through midweek with locally fresh gusts over the northern outer waters. Winds increase Friday into the weekend with near gale to gale force gusts likely. Seas will build in response to increasing winds and become rough. Additionally, southerly swell will impact the coastal waters starting Tuesday night with long period southerly swell increasing Friday into the weekend.

FIRE WEATHER

Issued at 306 AM PDT Mon Oct 5 2026

Strong ridging aloft will lead to hot and dry conditions through Thursday with elevated fire weather conditions across the higher elevations. Poor to very poor overnight humidity recoveries will continue across the thermal belts with pushes of offshore flow each morning. Hazardous heat will continue through Thursday with major to extreme risks of heat-related illnesses across most mountain ranges. A pattern change later this week will bring cooler conditions to the region.

MTR WATCHES/WARNINGS/ADVISORIES

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

Coastal Flood Advisory until 1 PM PDT Thursday for CAZ506.

PZ...None.