textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1251 PM PST Sun Jan 18 2026

- Dry weather, cool mornings, and warm afternoons this week

- Morning fog across the Delta, North Bay Valleys, and interior East Bay Valleys

SHORT TERM

Issued at 1251 PM PST Sun Jan 18 2026 (This evening through Monday)

Temperatures continue to warm as mostly sunny sky conditions have returned to the region. However, there are still high clouds streaming in from the northwest. As such, temperatures are likely to warm into the low to upper 60s across the North Bay, East Bay, and greater San Francisco Bay Area. Across the Central Coast, temperatures are likely to warm into the low to mid 70s.

Tonight, look for tule fog to return to the interior East Bay Valleys and Delta (similar timing as the previous nights) and continue through midmorning on Monday. Fog may also impact the North Bay Valleys in response to fog development in the Russian River Valley and/or tule fog advecting in from the east.

Monday's afternoon temperatures will be similar to those today (Sunday) as the region continues to be under the influence of high pressure. This ridge axis extends all the way up to just off of the British Columbia coast. However, high clouds will persist over the region through at least midweek.

LONG TERM

Issued at 1251 PM PST Sun Jan 18 2026 (Monday night through next Saturday)

By mid to late week, troughing will develop out over the north central Pacific. This feature is forecast to develop a cut-off upper level low that will gradually approach the region late in the week. However, there does not appear to be much of a moisture source associated with it, so rainfall has been pushed back until at least Monday, January 26th. With that said, the low pressure system aloft will at least cool temperatures down to near seasonal averages after a prolonged period of very warm afternoon temperatures. Thus, we will have to wait a bit longer for much needed rainfall to return.

AVIATION

(18Z TAFS) Issued at 902 AM PST Sun Jan 18 2026

Fog and stratus continues to mix out across the North and East Bay valleys with lingering impacts at CCR for the next couple of hours, but the TAF sites remain VFR through the day. Winds will remain light to gentle with a weak onshore breeze near the coast and offshore winds persisting inland. Fog and stratus return to the North and East Bay valleys tonight with haze expected at LVK. High resolution model data depicts some chance for stratus development in the San Francisco Bay, but this is a low confidence forecast at this time.

Vicinity of SFO... VFR through the day. High resolution model output is attempting to place a patch of stratus within the San Francisco Bay, but impacts to the terminal are highly uncertain and opted to leave the VFR TAF intact for now. Chances for stratus diminish after 18-21Z on Monday morning. Winds remain light with offshore flow predominant through the afternoon until mild onshore flow develops late this evening.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... VFR through the TAF period. Light westerly winds through the afternoon and evening, with breezy valley drainage winds developing overnight.

MARINE

(Today through Friday) Issued at 837 AM PST Sun Jan 18 2026

Gentle to moderate northeast to east breezes continue across the San Pablo Bay, the Delta, and through the Golden Gate through Wednesday while light to gentle northeast to north winds continue across the rest of the coastal waters. Later this week, the ridge should break down as a weak cutoff low approaches, allowing winds to increase and shift to the northwest and west. Low seas up to around 6 feet continue through the middle of the week as a northwest swell builds.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...None.