San Francisco’s Halloween forecast starts cool and cloudy, with temperatures around 55 degrees Saturday morning, while the Bay Area should remain dry into the afternoon. Highs should reach near 64 degrees. The key timing to watch is the afternoon high tide, followed by a chance of showers late Saturday night.
Coastal flooding concerns for Bay shoreline areas extend through 6 p.m. Saturday. Saturday’s high tide at the San Francisco gauge is expected around 3:44 p.m., about 1.5 feet above normal, with possible flooding near shorelines and tidal waterways.
Halloween: Showers Possible Into Early Sunday
Showers are possible Saturday into early Sunday.
The forecast points to a mostly dry start for trick-or-treaters and Halloween events, with temperatures sliding toward the low 50s later in the evening. A light jacket may be useful. The overnight timing adds detail to earlier Hoodline coverage, which noted the possibility of showers over the holiday weekend.
High Tide May Affect Bayshore Areas
The advisory covers bayshore locations along San Francisco Bay, San Pablo Bay and Monterey Bay. High water could affect low-lying infrastructure, prompt isolated road closures or contribute to coastal erosion. People traveling near the Embarcadero, shoreline paths or tidal waterways should allow extra time, follow posted barricades and avoid driving through water of unknown depth.
What City Planning Says About Shoreline Exposure
The City and County of San Francisco’s sea-level-rise guidance identifies filled shoreline areas including the Embarcadero, Mission Bay, SFO and Treasure Island as especially at risk from sea-level-rise-related hazards. It describes potential effects including rising groundwater, subsidence and liquefaction; that planning assessment does not mean these areas will flood during this advisory.
Sunday is forecast to be sunny, with a high near 63 degrees. The San Francisco gauge is expected to reach another high tide around 3:59 p.m., about 1 foot above normal; potential waterfront impacts may therefore extend beyond Saturday night’s rain window.
Rain Chances Return Next Week
Monday is forecast to be mostly sunny, with temperatures reaching about 65 degrees. Rain chances remain uncertain early to midweek, with low-probability chances later in the outlook.
