Marine Weather and Tide Forecast for Pacifica, CA

SHORT TERM
(Today and tonight)
Issued at 111 AM PDT Wed May 21 2025

Conditions are warmer and drier than they were this time last night, but only in the higher terrain. Why? Well, last night there was a shallow marine layer that impacted coastal areas while tonight the region is clear and winds are calm, allowing for maximal radiational cooling. A low amplitude upper-level shortwave ridge will trek across the region today, bringing the warmest conditions of the week. Temperatures will be 10 degrees above normal with widespread minor HeatRisk and areas of moderate HeatRisk for the Interior Bay Area and Central Coast. Elevated fire weather conditions will continue through tomorrow for the Interior Bay Area and Central Coast as dry conditions (poor daytime relative humidity of 15-25%, overnight relative humidity recovery of 30-50% in the higher terrain) and moderate to strong onshore winds continue. The threat is primarily in the finer, flashier fuels of brush and grass as recent offshore flow and warm conditions continue to cure them.

LONG TERM
(Thursday through Tuesday)
Issued at 111 AM PDT Wed May 21 2025

The lack of a longwave pattern over the region is evident in the extended forecast. An upper-level shortwave trough will skirt the region Thursday, causing temperatures to return to seasonal normals.
A second, deeper upper-level shortwave trough will dig into the region Friday, bringing the coolest conditions of the week. An upper- level longwave ridge builds into the West Saturday which will bring temperatures up to 5 degrees above normal. Global ensemble clusters show an Omega Block, the combination of two cutoff lows with one blocking high sandwiched between them, developing by Sunday. By nature, this will lead to uncertainty and low confidence in the progression of the longwave pattern into early next week as these features have very weak forcing and thus can be persistent.

AVIATION
(12Z TAFS)
Issued at 404 AM PDT Wed May 21 2025

Currently a mix of IFR-VFR at the terminals. High pressure is allowing for clear skies outside of the Monterey Bay where a compressed/shallow marine layer has returned. High confidence in widespread VFR by late-morning and onshore winds prevailing through the TAF period.

Vicinity of SFO...Currently VFR with westerly flow. High confidence in VFR and westerly winds prevailing through the TAF period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR with southwesterly flow at MRY and IFR with westerly flow at SNS. High confidence in VFR prevailing by late-morning. Low to moderate confidence on the return of IFR ceilings tonight with probabilities only in the 20-50% range.
Onshore winds will prevail through the TAF period.

MARINE
(Today through Monday)
Issued at 404 AM PDT Wed May 21 2025

Hazardous marine conditions continue today as strong northwesterly breezes with near gale to gale force gusts and rough to very rough seas persist. Winds will slowly diminish and seas will slowly abate tonight with fresh northwesterly breezes with strong gusts and moderate to rough seas prevailing Thursday through Sunday.

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this evening for Mry Bay.

Small Craft Advisory until 3 AM PDT Thursday for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

Gale Warning until 3 PM PDT this afternoon for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Thursday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.