textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 139 PM PDT Sat Oct 17 2026

- Very warm temperatures continue today

- Hazardous beach conditions through at least this weekend

- Much cooler weather arrives Sunday with rain chances midweek

SHORT TERM

Issued at 139 PM PDT Sat Oct 17 2026 (This evening through Sunday night)

This afternoon is shaping up to be another very warm day with temperatures reaching into the upper 80s to low 90s across the interior, around the Santa Cruz region, and Monterey Bay region. Temperatures reached the low 90s around Monterey region as onshore flow was delayed. However, the onshore flow has returned cooling temperatures into the upper 70s to mid 80s. The immediate coastline is forecast to remain in the low-to-upper 70s. That said, the high pressure over northern California is weakening and will continue to do so through the remainder of the weekend.

The cooling trend will be more robust tonight and into Sunday as a dry frontal boundary moves across the Bay Area and north Central Coast. This will also allow for a slightly stronger onshore flow and deepening marine layer (albeit temporarily) and more seasonable temperatures. Thus, temperatures will be some 10-15 degrees or more cooler than today.

LONG TERM

Issued at 139 PM PDT Sat Oct 17 2026 (Monday through next Friday)

A more robust cool down will occur Monday as the upper-level trough deepens off of the West Coast, bringing temperatures to below seasonal averages. The trough becomes a cut-off low by Tuesday with its center approximately 350 miles west of San Francisco. This will bring a cold front through the region Monday night into Tuesday morning as the center of the low pressure system pushes inland across the south Central Coast and/or southern California Wednesday evening into Thursday. This will result in unsettled weather conditions across the region Tuesday through Thursday.

As far as precipitation and thunderstorm chances go, there is a 20- 40% chance of rain showers across the greater Bay Area and 30-60% chance across the Central Coast. The greatest potential for convection is now on Wednesday when the core of the low begins to move onshore. The greatest potential (generally 15% or less) will be over the offshore waters and Central Coast where the greatest instability will be located.

A further offshore and southern track of the low pressure system would result in less rainfall and lower probability for convection. However, if it were to move directly into the Central Coast (or even the Bay Area) we would have stronger winds, heavier rain, and increased potential for thunderstorms. Thus, be sure to check back on the forecast as the event draws nearer.

AVIATION

(18Z TAFS) Issued at 1002 AM PDT Sat Oct 17 2026

Currently VFR. Moderate confidence on LIFR conditions returning to the coastal terminals of HAF, MRY, and SNS tonight. The atmosphere will need to undergo a lot of change over the next 18 hours for this to happen coming off of hot and dry conditions with no marine layer. Upstream observations show some stratus and fog, but a pattern change with an increase in wind and mixing will likely make it more difficult for the marine layer to reform. Diurnal winds will prevail. Haze will reduce slant range visibilities.

Vicinity of SFO...Currently VFR with northerly flow. High confidence in VFR through the TAF period. Northerly flow will back through the morning to become westerly with the sea breeze this afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with southwesterly flow at MRY and VFR with southeasterly flow at SNS. Moderate confidence on LIFR conditions returning to the terminals tonight. Diurnal winds will prevail.

MARINE

(Today through Thursday) Issued at 1002 AM PDT Sat Oct 17 2026

Moderate to fresh northwesterly breezes will prevail through Monday with strong breezes across the northern outer waters. Widespread hazardous conditions will spread across the coastal waters as a result Sunday afternoon, likely continuing into Monday. Moderate seas will prevail across the inner waters with rough seas building across the outer waters Saturday through Monday, rebuilding again Tuesday. Light rain is expected Monday night through Wednesday.

BEACHES

Issued at 1002 AM PDT Sat Oct 17 2026

Hazardous beach conditions will be present at Pacific Coast beaches through Sunday and likely into next week. Long period southerly/southwesterly swell will bring an increased risk for sneaker waves and strong rip currents with breaking waves of 7 to 12 feet. Remain off jetties, piers, rocks, and other waterside infrastructure as waves can sweep across the shoreline without warning, pulling people into the sea. Remain out of the water to avoid hazardous surf with strong rip currents and never turn your back on the ocean!

Sarment

MTR WATCHES/WARNINGS/ADVISORIES

CA...Beach Hazards Statement through Sunday evening for CAZ006-505- 509-529-530.

PZ...Small Craft Advisory from 3 AM to 9 PM PDT Sunday for Pt Arena to Pt Reyes 0-10 nm.

Small Craft Advisory from 3 PM to 9 PM PDT Sunday for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory until 9 PM PDT Sunday for Pt Arena to Pt Reyes 10-60 NM.