Tsunami warning lifted after 7.0-magnitude earthquake off Northern California coast
What we're covering
• A powerful earthquake with a preliminary magnitude of 7.0 struck off the coast of Northern California late Thursday morning local time, according to the US Geological Survey. A quake this strong is relatively rare, with officials reporting only about 15 around the world each year.
• A tsunami warning that was issued for parts of California and the Oregon coastline was canceled by the National Tsunami Warning Center after some residents fled their homes. Most significant off-coast quakes prompt such warnings, as experts have little time to determine the immediate risk, and the result of a tsunami could be disastrous.
• The quake’s epicenter was in the Pacific Ocean south of Eureka, California, the USGS said. Eureka is the largest coastal city between San Francisco and Portland, Oregon, and about 300 miles northwest of Sacramento.
What to know about the 7.0-magnitude earthquake that struck off the coast of Northern California
A strong earthquake with a preliminary magnitude of 7.0 shook the coast of Northern California on Thursday, triggering a tsunami warning for millions of people.
The tsunami warnings have since been canceled, and officials from the US Geological Survey said they have not had reports of landslides or other significant damage.
Here’s what we know:
- The earthquake: The epicenter of the earthquake was around 50 miles southwest of Eureka, California, in the Pacific Ocean, according to the USGS. Eureka is the largest coastal city between San Francisco and Portland, Oregon, and located about 300 miles northwest of Sacramento.
- Tsunami warnings: Nearly 5 million people were under a tsunami warning from Davenport, California, up to Douglas/Lane Line, Oregon, according the National Tsunami Warning Center. This included the San Francisco Bay Area, Eureka, Fort Bragg, and Crescent City, California.
- What happened: Tectonic plates well off the coast of the state moved in opposite directions, Stephen DeLong, a supervisory research geologist at the USGS, explained. That movement was likely mostly horizontal, rather than vertical — and vertical movement is the type that tends to cause tsunamis, he said. USGS data showed that the earthquake produced “severe shaking,” with residents telling CNN they felt the trembling as far south as the Bay Area.
- Aftermath: More than 3,000 customers in Humboldt County, California, the closest county to the epicenter of the earthquake, are still without power, according to PowerOutage.us. That’s down from around 10,000 homes and businesses that lost service there shortly after the quake. California Gov. Gavin Newsom declared a state of emergency to help provide resources.
- What officials are saying: Eureka, California, City Manager Miles Slattery said there has not been significant damage reported there so far, and described the quake as “long,” but not as “violent” as previous events. Another resident of Eureka said he felt seasick from the earthquake vibrations. There have also been no reports of injuries or damage in San Francisco, according to Capt. Justin Schorr of the city’s fire department.
- What could happen next: While aftershocks are happening near the epicenter of the earthquake, it is unlikely there will be additional earthquakes of a 7 magnitude, seismologist Jeffrey Park told CNN. Still, there could be some smaller earthquakes along the faults, he said.
This post has been updated to reflect the latest power outage total in Humboldt County.
Biden briefed on Northern California earthquake
President Joe Biden was briefed on the 7.0 magnitude earthquake off the coast of northern California, White House spokesperson Jeremy Edwards said Thursday.
“At his direction, Senior Administration and FEMA Regional officials are in touch with their state and local counterparts in California and Oregon,” Edwards said in a statement. “We stand ready to provide further support as needed — at this time there are no requests for federal assistance.”
The White House told residents to “remain vigilant and listen to local officials.”
Backyard pool shakes as 7.0 magnitude earthquake rocks parts of Northern California
Footage captured by California resident Wren Raftery shows her backyard pool shaking Thursday in Chico, a city about 90 miles north of Sacramento.
Raftery told CNN she was in her living room when she got the earthquake alert on her phone at around 10:45 a.m. PST. She was with her 13-year-old daughter, who was at home sick.
About 10 seconds after she received the alert, Raftery said she experienced some slight shaking. She and her daughter then stepped outside to her backyard pool where she “felt the earthquake stronger.”
But Raftery said she then felt a second shaking, which she described as “mild,” about 5 minutes after the first one. This prompted her and her daughter to run back into the house. The second shaking barely lasted 10 seconds, though it left her feeling dizzy for an hour, Raftery told CNN.
“I was feeling dizzy for an hour. I felt my equilibrium was off,” Raftery said at the end of the second quake, which stopped roughly before 11:00 a.m. PST.
Raftery said she later received a message from her 10-year-old’s fifth-grade teacher informing parents that “all the students did a good job getting under their desks to be safe and were able to feel the quake.” Raftery, who was born in Chico and has lived there nearly her entire life, said that she has not heard reports of any damage in the town after speaking with her family.
Ferndale resident describes her car "jumping about" after earthquake hit area
As an earthquake rattled Ferndale, California, resident Caroline Titus rushed out of her home to find her car was “jumping about” and a power transformer had blown, leaving her neighborhood without power, CNN affiliate KGO reports.
She immediately ran down the block to her granddaughter’s pre-school building. When she arrived, the children were huddled under an outdoor play structure and a teacher was calming them by singing the ABCs, Titus told the affiliate.
The town has “miraculously” not sustained severe damage, Titus said. Building windows remained intact and “it’s just stuff off the shelves,” she said.
After the transformer blew down the street, the neighborhood was without power for about 30 minutes, she said. At one point, more than 10,000 homes and businesses in Humboldt County, where Ferndale is located, were without power, according to PowerOutage.us.
“We really dodged a bullet on this one,” she told CNN, adding that the residents “consider ourselves lucky.”
Gov. Newsom declares state of emergency to help provide resources
California Gov. Gavin Newsom declared a state of emergency in response to Thursday’s earthquake in Northern California. The move allows resources to move more freely to aid with any damage that occurred.
Early damage assessments are still underway, and the state is working with teams on the ground, he said.
“It’s another reminder of the state that we live in and the state of mind we need to bring to our day to day reality,” Newsom said.
USGS describes what happened during the earthquake off the California coast
The US Geological Survey said the earthquake that struck off the coast of Northern California was typical of the area, and it has not received any detailed reports of damage or landslides related to the event as of right now.
In a briefing on Thursday, Stephen DeLong, a supervisory research geologist at the USGS, said the earthquake occurred “well off shore.” The epicenter of the quake was about 50 miles southwest of Eureka, California, over the Pacific Ocean, the USGS previously said.
DeLong said the tectonic plate to the north moved to the right and the plate to the south moved to the left.
Still, estimates and data shows that there were intensity 8 levels of shaking, which is considered “severe shaking,” according to Robert de Groot, the ShakeAlert national coordinator for communication, education and outreach at USGS.
People could have seen things falling off of shelves, furniture being moved or windows breaking, he said.
San Francisco's BART reports some delays after earlier warning about major disruptions
As tsunami warnings were issued for the San Francisco area following the earthquake, Bay Area Rapid Transit, or BART, announced it was experiencing significant service disruptions that included cancellation of service along its underwater rail line, the Transbay Tube.
Service was resumed after the tsunami warning was canceled, but riders should still plan for an approximately 20-minute delay as the transportation system recovers, BART said.
BART provides transit that connects the San Francisco Peninsula to the East and South Bay. On an average weekday, about 150,000 riders use the service, though it is unclear how many people are impacted by the current delays.
The headline and post have been updated with the latest information from BART.
Eureka resident says he felt seasick from earthquake vibrations
One resident in Eureka, California, experienced vibrations from the earthquake for about 30 seconds, he told CNN, describing the event as “long and rolling.”
At the end of the quake, the vibrations were so small that John Wrigley said he felt almost seasick, as if he was on a ship.
The earthquake was not sharp in nature, Wrigley said, and he didn’t experience any damage to his home.
After speaking with neighbors and other friends in the community, Wrigley — who has lived in Humboldt County nearly his entire life — had not heard reports of any damage elsewhere in the coastal town. The Eureka city manager has also told CNN there were no immediate reports of damage.
Wrigley, who has experienced roughly 10 earthquakes while living in the county, said Thursday’s was the longest one he’s experienced there.
Why the tsunami warning was canceled after people were told to evacuate
Coastal residents in Northern California and Oregon felt extreme whiplash Thursday when, within a single hour, a 7.0-magnitude earthquake struck off the coast of Eureka, a tsunami warning was posted, officials urged people to pack go-bags and head a mile inland, and then the tsunami warning was canceled.
The immediate warning was evidence of how disastrous a tsunami would be, particularly along the highly populated West Coast, and how important it was to get that message out as soon as possible — even before anyone knew whether a tsunami was on the way.
Underwater earthquakes of this magnitude have a very high likelihood of strong vertical movement: the ocean floor jerks upward or downward and jolts the water around it, generating a tsunami.
But it’s hard to tell whether that’s happened in the minutes after the earthquake strikes — and those minutes are precious time people need to be warned to evacuate.
This is why you’ll see most off-coast earthquakes come with a tsunami warning, just in case.
Geophysicists would much rather get the warning out and cancel it than give people too little time to get to safety.
Until scientists know for certain that there is no danger, the message to everyone along the coast has to be, “Get to higher ground.”
Seismologist: Large aftershocks are unlikely, but smaller earthquakes across fault lines could happen
While aftershocks are happening near the epicenter of Thursday’s earthquake, it is unlikely there will be additional earthquakes of a 7 magnitude, seismologist Jeffrey Park told CNN.
It is possible that, since the earthquake redistributed the stress in the surrounding fault lines, there may be some smaller earthquakes on the faults, he said.
“Some of the earthquake faults could get better in the region very close to where the rupture occurred. But also in some of the other faults that are maybe even on shore could have earthquake activities. Smaller earthquakes, but because they might occur on land would be more damaging to the buildings above them,” Park said.
There are no reports of injuries or damage in San Francisco so far, fire captain says
There are so far no reports of injuries or damage in San Francisco after today’s powerful Northern California earthquake, according to Capt. Justin Schorr of the city’s fire department.
The quake, with a preliminary magnitude of 7.0, struck nearly 300 miles up the coast near the town of Eureka, according to the US Geological Survey.
Tsunami warnings were immediately issued along the Northern California and Oregon coastlines but were dropped about an hour later. As the warnings were in effect, San Francisco fire personnel urged coastal residents to seek higher ground, Schorr said.
“This was not a false alarm,” Schorr said, addressing the tsunami warnings. He noted the fire department ensured residents were well aware of the possible safety risks and adhered to alerts from the US Geological Survey and National Tsunami Warning Center.
This post was updated with more information from the San Francisco Fire Department.
No significant damage reported in Eureka, California, so far, city manager says
The city manager of Eureka, California, said there has not been significant damage reported there so far, after an earthquake with a preliminary magnitude of 7.0 struck off the coast near the northern city.
Miles Slattery told CNN there have not been any calls for broken gas lines or significant structural damage so far. He described the quake on Thursday as “long,” but not as “violent” as previous events, namely those with an epicenter on land.
The earthquake hit off the coast, about 60 miles southwest of Ferndale, California, the US Geological Survey said. Eureka is located about 19 miles north of Ferndale, and some 300 miles north of San Francisco.
Parts of the California and Oregon coast, including Eureka, were under a tsunami warning in the minutes following the powerful quake. The warning has since been canceled, but Slattery said part of the town was evacuated.
Some background: In December 2022, a 6.4 magnitude earthquake struck Northern California’s Eureka area, the US Geological Survey said, leaving at least two people dead, drawing reports of damage to roads and homes, shaking residents from their sleep and leaving tens of thousands without electricity.
Less than two weeks later, a 5.4 magnitude earthquake occurred about 30 miles south of Eureka and was centered about 9 miles southeast of Rio Dell, the USGS said.
Tsunami warning canceled for California and Oregon
The tsunami warning for California and Oregon’s coastal areas has been canceled, according to the National Tsunami Warning Center.
A small change in ocean height of several inches was recorded by an ocean buoy around 200 miles off the coast of California, but no significant change was recorded on shore, prompting the cancellation of the warning.
Aftershocks rumble across California
There have been at least six aftershocks in the last 10 minutes, including a 4.2-magnitude quake near Petrolia, California.
At least a dozen aftershocks have taken place since the original 7.0-magnitude quake occurred at 10:44 a.m. PT.
Over 10,000 outages in Humboldt County
There are over 10,000 customers without power in Humboldt County, California, the closest county to the epicenter of Thursday’s earthquake, according to PowerOutage.us.
That’s about 10% of the customers tracked in the county by the outlet.
There are no notable outages in the surrounding counties.
Officials still evaluating tsunami risk to parts of California's central and southern coast
Officials are still evaluating whether large counties in central and Southern California face any risk of tsunami impacts after a powerful earthquake struck in the far northern part of the state, according to the National Weather Service.
That message came as an update to an earlier message from the office, which had said there was no tsunami threat to those areas.
The quake — which had a preliminary magnitude of 7.0, according to the US Geological Survey — struck near Eureka, California, which is nearly 300 miles north of San Francisco.
Just 15 quakes of 7.0 magnitude occur per year around the globe
There are only about 15 earthquakes that reach the 7.0 magnitude range per year, according to CNN’s Chad Myers and the United States Geological Survey.
“But they typically don’t happen so close to land; this one was not very far offshore,” Myers said.
He added that a 7.0-magnitude earthquake is considered a strong, borderline major quake.
Seismologist: People in affected areas should take tsunami warning "very seriously"
One seismologist is warning people along parts of the coast of California and Oregon that the tsunami warnings in effect are “something to take very seriously.”
Maureen Long, who is also a professor of earth and planetary sciences at Yale University, said the most important thing is to “be aware.”
The National Tsunami Warning Center issued a warning after a powerful 7.0 magnitude earthquake struck off the coast of Northern California on Thursday. Nearly 5 million people are under that warning from Davenport, California, up to Douglas/Lane Line, Oregon, the agency said. This includes the San Francisco Bay area, Eureka, Fort Bragg, and Crescent City, California.
Tsunami activity is likely reaching the coastline now, according to forecasts. Long said the reason for that delay — between the earthquake and potential tsunami impacts — is because earthquake waves travel faster.
A tsunami wave “in the open ocean tends to travel about as fast as a jet plane flies, whereas earthquake waves travel much faster,” she said. That delay means it is easier for experts to issue tsunami warnings, Long said.
FEMA administrator briefed on earthquake and tsunami warning
Federal Emergency Management Agency Administrator Deanne Criswell has been briefed on the 7.0-magnitude earthquake in Northern California that has prompted tsunami warnings, a spokesperson for the agency said on social media.
“Please listen to local officials and heed their warnings,” FEMA spokesperson Jaclyn Rothenberg wrote on social media.
The epicenter of the quake was about 50 miles southwest of Eureka, California, over the Pacific Ocean, the US Geological Survey said. There is a tsunami warning in effect for parts of the California and Oregon coastline, according to the National Tsunami Warning Center.
Tsunami warning in effect for parts of California and Oregon
A tsunami warning is in effect as a result of the recent 7.0-magnitude earthquake off the coast of Northern California.
Nearly 5 million people are under the tsunami warning from Davenport, California, up to Douglas/Lane Line, Oregon, according the National Tsunami Warning Center. This includes the San Francisco Bay area, Eureka, Fort Bragg, and Crescent City, California.
Tsunami activity is likely reaching the closest coastlines now, and should reach San Francisco in one hour. The following locations are forecast to see tsunami activity begin at these specified times:
California
- Fort Bragg: 11:10 a.m. PT
- Crescent City: 11:20 a.m. PT
- San Francisco: 12:10 p.m. PT
Oregon
- Port Orford: 11:20 a.m. PT
- Brookings: 11:25 a.m. PT
- Charleston: 11:40 a.m. PT
San Francisco Zoo closed as tsunami warning put into effect
The San Francisco Zoo is closed after a powerful earthquake struck off the coast of Northern California on Thursday, it said in a post on X.
There is now a tsunami warning in effect for parts of the California and Oregon coastline, the National Tsunami Warning Center said. That warning includes San Francisco.
The zoo said guests have been evacuated and it has secured the animals, according to the post.
Here's how earthquakes happen
The US Geological Survey describes an earthquake as “the ground shaking caused by a sudden slip on a fault. Stresses in the earth’s outer layer push the sides of the fault together. Stress builds up and the rocks slip suddenly, releasing energy in waves that travel through the earth’s crust and cause the shaking that we feel during an earthquake.”
Earthquakes are measured using seismographs, which monitor the seismic waves that travel through the Earth after an earthquake strikes.
Scientists used the Richter Scale for many years to measure earthquakes, but now largely follow the “moment magnitude scale,” which USGS says is a more accurate measure of size.
The most recent significant earthquake to cause widespread damage was reported on October 7, 2023, west of the city of Herat in Afghanistan. It was a 6.3-magnitude tremor that left more than 2,000 people dead, according to officials.
Today’s earthquake in Northern California had a preliminary magnitude of 7.0, according to the US Geological Survey — though magnitudes are often adjusted after initial reports.
Click here for a look at the most significant earthquakes over history.
State and local officials responding to Northern California earthquake
California officials are responding to earthquake activity in the northern part of the state on Thursday, Gov. Gavin Newson said in a post on X.
The California Governor’s Office of Emergency Services is coordinating with local officials in Humboldt and Lake counties, where earthquake activity was reported, it said in a separate post. The state and local personnel will “assess impacts” of the earthquakes, it added.
The largest of the quakes felt in Northern California on Thursday had a preliminary magnitude of 7.0, according to the US Geological Survey. Earthquakes frequently occur in clusters.
Strong earthquake shakes Northern California coast
A strong earthquake with a preliminary magnitude of 7.0 has occurred around 50 miles southwest of Eureka, California over the Pacific Ocean, according to the USGS.
There is a tsunami warning in effect for parts of the California and Oregon coastline according to the National Tsunami Warning Center.
Here's how tsunamis are formed
Tsunamis are formed by a displacement of water — a landslide, earthquake, volcanic eruption, or slippage of the boundary between two of the earth’s tectonic plates, slabs of rock 50 to 650 feet (15 to 200 meters) thick that carry the Earth’s continents and seas on an underground ocean of much hotter, semi-solid material.
Tsunamis can travel more than 500 mph (800 k/ph) at the deepest point of the water, but slow as they near the coast, eventually hitting the shore at 20 to 30 mph (32 to 48 k/ph). The energy of the wave’s speed is transferred to height and sheer force as it nears shore.
The most recent tsunami to cause widespread devastation was in December, 2018, when a tsunami with waves as high as about 10 feet (3 meters) hits Pandeglang, Serang, and South Lampung, Indonesia, leaving more than 437 people dead, 16 missing and 16,198 displaced.
Click here for a list of notable tsunamis in the past
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