Tsunami Warning Issued for Northern California

The National Weather Service issued an upgraded tsunami warning Tuesday night for a 100-mile stretch of Northern California’s coastline between Cape Mendocino and the border with Oregon after a rare 8.8 magnitude earthquake struck of Russia’s eastern coast.

Officials warned that waves of up to five and a half feet high were expected to reach the coast at Crescent City in Northern California, about 20 miles south of the Oregon border, just before midnight Pacific time. The Weather Service urged residents in the warning zone to move inland away from coastal areas.

That stretch of the Northern California coastline has had frequent experiences with tsunamis over the past century. A tsunami warning means that dangerous coastal flooding and powerful current are possible and may continue for several hours or days.

Crescent City, which has a population below 7,000, was particularly vulnerable to tsunamis because of its low elevation on land that juts out to the sea. It has been hit by 32 tsunamis since 1933. Five of them caused damage, according to a city website, and the one that hit in 1964 was devastating, killing 11 people and destroying 29 city blocks, a county website states.

Lori Dengler, an emeritus professor of geology at California State Polytechnic University, Humboldt, said that the city was in the process of “an orderly evacuation of the commercial fishing fleet” on Tuesday evening.

Nearly the entire rest of the West Coast is under a tsunami advisory, a lower alert level, meaning that flooding of beaches and harbor areas was possible but widespread inundation was not expected. Most of California’s coastline is expected to experience waves of less than two feet.

Mary Ellen Carroll, the executive director of San Francisco’s Department of Emergency Management, said the waves there are only expected to be one foot high, but they could still pose a danger because of strong riptides and currents.

She said she was generally not concerned — except for those who ignore guidance to stay out of the water.

“We want to make sure swimmers, surfers, kite surfers, all those folks get on shore and stay off the beaches,” she said, adding that port officials were warning people who live on houseboats near the Giants ballpark to be ready to leave if necessary.

She said the National Park Service was closing all San Francisco beaches on Tuesday night and would likely keep them closed on Wednesday. The local ferry system was also warned to stay alert about whether to send boats out Wednesday morning.

“We’re a little bit lucky that this is going to start in the middle of the night when most people are not out,” Ms. Carroll said, noting waves should hit the city around 1 a.m. She added they could last anywhere from a few hours to 36 hours.

“Stay calm,” Mayor Daniel Lurie of San Francisco said in a video on Instagram. “We are ready.”