Tsunami warning issued after strong California earthquake

(NEXSTAR) – The National Weather Service issued a tsunami warning Thursday for a large stretch of California coastline following a strong earthquake near Eureka.

The tsunami warning, which blared on many California residents' phones at 10:50 a.m., warned people to move away from coasts. The affected area stretched from southern Oregon through the Bay Area and down to Davenport, just north of Santa Cruz.

"You are in danger. Get away from coastal waters. Move to high ground or inland now. Keep away from the coast until local officials say it is safe to return," the warning read.

The tsunami threat was triggered by an earthquake with an epicenter about 40 miles southwest of Ferndale in Humboldt County. The USGS gave the earthquake a preliminary magnitude of 7.0, though it could be revised in the hours to come.

"It started out shaky and then turned into a rolling one," said Humboldt resident Katie Hall. "It seemed like it went on forever."

The large earthquake was followed by several, smaller aftershocks.

The red shaded area on the maps above, provided by the U.S. Tsunami Warning System, show the coastal communities under the tsunami warning.

In the Bay Area, the warning affects more than just the cities along the Pacific coastline. It also impacts communities neighboring the San Francisco, San Pablo and Suisun bays.

The potential tsunami start times range depending on location. The National Weather Service estimated the big waves could reach Fort Bragg at 11:10 a.m., Crescent City at 11:20 a.m., and San Francisco at 12:10 p.m. Cities in southern Oregon were expected to be impacted starting between 11:20 a.m. and 11:40 a.m.

Even as those times pass, the threat isn't over, the National Weather Service warned.

"Tsunamis are a series of waves dangerous many hours after initial arrival time," the agency wrote. "The first wave may not be the largest."

Nexstar's Bill Disbrow contributed to this report.