Dangerous Sneaker Waves Forecast To Hit Marin, Bay Area Coast

MARIN COUNTY, CA — The National Weather Service is warning of a high risk of sneaker waves Tuesday and Wednesday along the entire Bay Area coastline, from the Sonoma and Marin coasts south to the Monterey Coast.

A beach hazards statement goes into effect at 6 p.m. Tuesday and continues through 8 p.m. Wednesday, with the weather service warning of "waves seemingly out of nowhere, catching beachgoers by surprise."

There is also a high risk of rip currents and marine debris ending up on beaches in the region, from Coastal North Bay and the Point Reyes National Seashore to the San Francisco Peninsula and Coast, and from the Northern Monterey Bay to the Southern Monterey Bay and Big Sur Coast, although the northern Monterey Bay will be somewhat sheltered from the swell, forecasters say.

The "very long period swell" will bring initial forerunner waves of 21 to 23 seconds to the Sonoma Coast starting late Tuesday afternoon before spreading south Tuesday evening, according to the National Weather Service San Francisco Bay Area.

"Wave heights will rise by Wednesday morning to 5 to 9 feet at a periodicity of 18 to 20 seconds," the weather service said. "This will result in a high risk of sneaker waves."

According to the weather service, sneaker waves can arrive every few minutes or can be 30 minutes apart and come during otherwise calm conditions.

Such waves may catch people on coastal jetties, rocks, piers or shorelines off guard and may injure them or knock them into the cold, turbulent ocean.

Strong rip currents are expected to accompany the energetic wave train, particularly at west-northwest facing beaches, including but not limited to: Ocean Beach, Montara State Beach, Half Moon Bay State Beach, Manresa State Beach and Marina State Beach.

"Beachcombing is not advised during this timeframe," the weather service said. "...These types of events claim lives each year so extreme vigilance is advised if visiting the coast."

Bay City News contributed to this report.