Marine Weather and Tide Forecast for Belmont, CA

SHORT TERM
(Today and tonight)
Issued at 1201 AM PDT Sat Apr 19 2025

The marine layer has compressed to around 500 feet, and the low stratus is confined mostly to the Bay Area coast. The marine layer is a little deeper across the central coast, where the stratus is filling the Salinas Valley. These clouds will clear in the afternoon and the temperatures will be near normal, similar to yesterday. A weak disturbance will arrive this evening, allowing the marine layer to deepen. As a result, cloud cover will be more extensive early Sunday morning. The offshore winds will also weaken as the gradient relaxes. This will allow more low-level moisture, and there could be patchy fog and even some drizzle across the region.

LONG TERM
(Sunday through Friday)
Issued at 1201 AM PDT Sat Apr 19 2025

The disturbance will quickly move through Sunday, allowing persistent zonal flow to become entrenched from Sunday afternoon through Tuesday. This will bring fair weather with mostly clear skies, gentle to moderate onshore winds, and high temperatures above seasonal normal. The typical warmer inland areas have a roughly even chance of breaking 80 degrees Monday. This warmer weather will cause minor HeatRisk, which can be hazardous to those extremely sensitive to the heat. Otherwise, this period will be pretty nice.

Ensembles are now in good agreement that the pattern will change mid week as a deep trough disrupts the subtropical high in the eastern Pacific. This system will bring a cooler air mass from the NW, causing surface temperatures to cool back below normal by Friday. The strength and timing of this trough is still uncertain, but it is looking more likely that some light rain will fall Friday-Saturday.

AVIATION
(06Z TAFS)
Issued at 1023 PM PDT Fri Apr 18 2025

Satellite shows low ceilings have pushed inland over Monterey Bay and along the coast causing IFR/MVFR conditions over KSNS, KMRY and KHAF. Most models show agreement of MVFR conditions building over most of the terminals (with the exception of KLVK) but there is some uncertainty as some offshore winds should keep things a bit on the drier side and keep the marine layer confined to the coast. VFR expected to return by 18Z for all terminals, but MVFR conditions are anticipated to return by Saturday night.

Vicinity of SFO...VFR currently, but low stratus has developed along the coast. Models vary with bringing MVFR ceilings in tonight.
Therefore, moderate confidence on MVFR building near 10Z, as there is a chance that a low SCT group may prevail through the night. If MVFR conditions occur, expect VFR near 17-18Z. MVFR ceiling will return by late Saturday night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals.. MVFR/IFR conditions will prevail until 18- 19Z, where VFR is expected to return. Timing is a bit uncertain as conditions may clear closer to 20Z. MVFR conditions may prevail through most of KMRY TAF period. Expect both terminals to see a return of MVFR by 03Z.

MARINE
(Tonight through next Thursday)
Issued at 845 PM PDT Fri Apr 18 2025

Northerly flow increases going into early Saturday, especially over the northern outer waters, as a weak cold front approaches from the north. The increasing winds will result in a building northerly fresh swell. Stronger northerly winds will last into the next week.

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...Small Craft Advisory until 3 PM PDT Sunday for Pt Arena to Pt Reyes 10-60 NM.