textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1129 AM PDT Sat Oct 31 2026

- Minor coastal flooding at high tide for Bayshore and Pacific Coast locations through the weekend

- Seasonal to slightly below seasonal temperatures through Thursday

- Potential for light rain Saturday night and again early in the upcoming week

SHORT TERM

Issued at 1129 AM PDT Sat Oct 31 2026 (This afternoon through Sunday)

Chances for rain showers remain greatest (20-50%) across the mountains of San Bentio County and interior portions of Monterey County through the rest of the day today. This is all head of a cold front that will approach from the northwest and move southeastward across the North Bay late this evening (between 7 - 11 PM PDT), across the rest of the Bay Area (between 11 PM PDT - 6 AM Sunday PST), and across the Central Coast (between 1 - 7 AM Sunday PST). As the front moves through the region overnight, there is a 10-20% probability of thunderstorms, largely over the coastal waters. Post frontal rain showers may linger offshore and along the Monterey County coastline through early Sunday afternoon. All in all, rainfall amounts are forecast to be on the light side through Sunday afternoon with the greatest probability of measuring >0.25" being in the coastal ranges and lesser amounts as you move farther inland.

By Sunday afternoon, expect mostly dry and clearing sky conditions as weak ridging builds in from the eastern Pacific in wake of the exiting trough. Temperatures will remain seasonably cool with afternoon highs in the 60s and overnight lows in the 40s to lower 50s with the coldest regions of the North Bay potentially reaching into the upper 30s both tonight and Sunday night. Again, coastal flooding remains possible along the bayshore locations of the San Francisco, San Pablo, and Monterey Bays through Sunday at 6 PM PST with the Pacific Coast dropping off at 6 PM PDT this evening. For more information on that please see the CFWMTR product.

LONG TERM

Issued at 1129 AM PDT Sat Oct 31 2026 (Sunday night through next Friday)

The next chance for rain across the region will be from early Tuesday morning through Wednesday morning as an upper level cut- off low approaches the northern California coast from the west. But again, not expecting widespread heavy rainfall from this system. The placement of the cut-off low remains in question from Monday night through Wednesday. A farther north track would result in less rainfall across the Bay Area and Central Coast vs. a more southern track. Dry weather now looks to return for the remainder of next week with a gradual warming trend heading into next weekend.

AVIATION

(18Z TAFS) Issued at 1111 AM PDT Sat Oct 31 2026

Breezy onshore winds this afternoon with VFR ceilings. Winds ease this evening ahead of the first few rainbands. Light rain showers are forecast to arrive between 11 PM PDT - 1 AM PST (06-08Z). Ceilings may lower as the rain approaches the coast, remaining mainly VFR with a chance of borderline VFR-MVFR decks. Impacts to visibility are also possible. Overall, medium confidence on rain impacts as this morning's 12Z KOAK sounding measured decreased moisture content compared to yesterday with dry air confined to the surface. Lower confidence on impacts at terminals in rain shadowed areas, such as SJC and LVK. Dry, VFR conditions prevail through Sunday morning with the potential for some lingering showers over Monterey Bay.

Vicinity of SFO...VFR with high clouds cruising through. Onshore winds increase this afternoon and ease in the evening. Moderate confidence for light rain showers to arrive at the terminals around midnight with lower VFR ceilings and slight visibility reductions. If rain develops overnight, expect improved conditions by Sunday morning with increasing moderate northwesterly breezes.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR as onshore winds increase this afternoon. Winds ease and shift southerly as light rain showers approach the terminals. If the rain materializes, borderline MVFR- VFR ceilings and visibility reductions are possible overnight with conditions improving by late Sunday morning.

MARINE

(Today through Thursday) Issued at 906 AM PDT Sat Oct 31 2026

Variable gentle to moderate breezes with moderate seas continue into early next week. By mid-week, northwest moderate to fresh winds are forecast with seas building to rough across the outer waters. The chance for light rain showers tonight into Sunday continue with another round possible Tuesday into Wednesday. A long period southerly swell remains this weekend and combines with a long period northwesterly swell on Monday.

MTR WATCHES/WARNINGS/ADVISORIES

CA...Coastal Flood Advisory until 6 PM PDT Sunday for CAZ006-506-508- 529-530.

Coastal Flood Advisory until 6 PM PDT this evening for CAZ505- 509.

PZ...None.