Marine Weather and Tide Forecast for Mountain House, CA

SHORT TERM
Issued at 321 AM PST Sun Dec 7 2025 (Today and tonight)

Rinse and repeat kind of weather for the short term. Very similar to what was observed 24 hours ago in the broader scheme of things.
Longwave pattern continues to show broad upper level ridging off the CA coast nosing its way into CA. A few high clouds are riding the northern periphery of the ridge. At the surface is where the impactful weather continues with and stratus covering the North Bay, East Bay, and portions of the Bay Area. Tule Fog is sneaking in from the Central Valley into the West Delta, North and East Bay. Patchy dense fog will be possible through mid morning with vsby less than one mile at times. The Central Coast on the other hand remains cloud free.

Stratus didn't really clear yesterday over the North Bay so that is the question for today? Will Santa Rosa see some sunshine? Latest guidance says yes, but very late in the day. As such, undershot max temps from the NBM for the North and East Bay with highs struggling to reach 50 degrees. Other locations will see more sunshine and warming temperatures into the mid 50s and 60s.

Expecting a similar pattern again tonight with some stratus and intruding Tule Fog.



LONG TERM
Issued at 321 AM PST Sun Dec 7 2025 (Monday through Saturday)

No major updates for the extended as we're locked in with this ridge of high pressure dominating the overall weather through at least next Friday. That means, some night and morning clouds like we've been having. Tule Fog will still advect into the Bay Area from time to time. The ridge is expected to build with higher heights. The stratus deck will compress with a gradual warming trend over the region. Still looking at 70 plus degrees across the Central Coast Tuesday through Friday. The amount of clouds cover over the North and East Bay will likely impact max temps and limit warming potential early in the week, but ease as the high pressure builds.

Rain chances still exist for the middle of the month, but odds are decreasing. Latest CPC has backed off with near normal or below normal chances for precip through December 20.

AVIATION
(12Z TAFS)
Issued at 342 AM PST Sun Dec 7 2025

Tule fog pattern still strongly dominating the region. Based on persistence, low confidence in actually clearing for North Bay terminals. These areas have a slight chance of seeing IFR/LIFR all day again today. High confidence in clearing for Bay Area terminals (sans KLVK), but stratus and fog will be patchy through sunrise.

Vicinity of SFO...Patch of stratus and fog moving along the peninsula likely to persist through sunrise, clearing to VFR in the few hours following. Otherwise quiet and clear through the afternoon with stratus returning this evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...High confidence in VFR through the TAF period. Light drainage offshore winds overnight with light onshore flow during the afternoons.

MARINE
(Today through Friday)
Issued at 321 AM PST Sun Dec 7 2025

Winds are reducing across the waters, but breezy northwest winds linger into the middle of next work week with the strongest winds focused on the southern waters. Moderate seas with wave heights 6 to 8 feet across the outer waters this weekend. A new, long period northwesterly swell is anticipated by Wednesday of next week.

MTR WATCHES/WARNINGS/ADVISORIES
CA...Coastal Flood Advisory until 3 PM PST this afternoon for CAZ006- 506-508-529-530.

PZ...Small Craft Advisory from 3 PM Monday to 3 AM PST Tuesday for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory from 3 PM this afternoon to 9 PM PST this evening for Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory from 9 AM this morning to 3 AM PST Tuesday for Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory until 9 PM PST this evening for Pigeon Pt to Pt Pinos 10-60 NM.