Northern California coast faces 16-foot waves as NWS issues beach hazards statement

High surf and sneaker waves threaten the coastline

The National Weather Service has issued a beach hazards statement for Northern California and the Central Coast, warning of massive breaking waves up to 16 feet, dangerous rip currents, and coastal flooding. The alert, which takes effect on Saturday at 7:00 am and runs until Monday at 2:00 pm, covers a vast stretch of the coastline, including San Francisco County, the North Bay, the San Francisco Peninsula, Northern and Southern Monterey Bay, and the Big Sur Coast.

Meteorologists at the agency's San Francisco office warned that the incoming swell will bring significant hazards to the shoreline. Beachgoers can expect sneaker waves—sudden, unexpectedly large waves that can sweep people off dry sand into the cold Pacific water—as well as powerful rip currents that can quickly pull swimmers out to sea.

Tidal surge to cause coastal flooding

The danger is heightened by high astronomical tides combined with a weather-driven surge of up to 1.2 feet. According to weather service predictions at the San Francisco tidal gauge, the peak of the high tide will rise significantly above normal levels over the coming days, pushing water further up the beach than usual.

On Friday morning, the tide is expected to reach 1.2 feet above normal, or 7.1 feet Mean Lower Low Water (MLLW). By Saturday at 11:50 am, it will peak at 1.4 feet above normal (7.3 feet MLLW), followed by a 1.3-foot anomaly (7.2 feet MLLW) on Sunday afternoon at 12:18 pm, and 1.2 feet (7.1 feet MLLW) on Monday at 12:46 pm. The elevated water levels are expected to persist into Tuesday afternoon.

This elevated sea level means high tides will push water and waves much further up the beach than typical. The weather service expects coastal flooding in low-lying areas, which could cut off access to some beaches, submerge coastal trails, and flood parks, car parks, and roads.

Safety advice for visitors

While only isolated road closures are anticipated, the weather service has advised drivers to allow extra travel time and avoid driving through water of unknown depth or bypassing barricades.

For those visiting the coast, the official advice is to stay well back from the water. Emergency officials have urged people to stay off jetties, piers, rocks, and other coastal structures, which can be easily overtopped by sudden waves. People are also advised to stay out of the water entirely to avoid the hazardous surf, and are reminded of a golden rule for the Pacific coast: never turn your back on the ocean.