On Thursday, the United States lifted a tsunami warning issued after a 7.0-magnitude earthquake struck off the northern California coast. The quake occurred about 100 kilometers (62 miles) west-southwest of Ferndale, at a depth of 10 kilometers (6 miles), as reported by the United States Geological Survey (USGS).
Residents were promptly alerted, with smartphone notifications advising them to seek higher ground. According to the San Francisco Chronicle, the warning stated: “A series of powerful waves and strong currents may impact coasts near you. You are in danger. Get away from coastal waters.”
Tsunami sirens sounded along coastal areas, including Bonny Doon in Santa Cruz County. Initial waves were expected to reach San Francisco around 12:10 PM local time (2010 GMT).
The National Weather Service’s Tsunami Warning Center in Honolulu issued a caution: “Based on preliminary earthquake parameters, hazardous tsunamis are possible for coasts within 300 kilometers of the earthquake epicenter.”
The earthquake, which struck at 10:44 AM local time (1844 GMT), was widely felt across the region, including the San Francisco Bay Area. Some residents reported strong shaking and rolling sensations.
Understanding the Earthquake and Tsunami Timing
Seismologist Maureen Long explained to CNN that the delay between the earthquake and tsunami waves occurs because of the differences in how energy travels. “Tsunami waves in the open ocean move at the speed of a jet plane, while earthquake waves travel much faster,” she noted. This time difference allows authorities to issue tsunami warnings in advance.
Eyewitness Reports and Regional Impact
Marc Buller, a lawyer from Eureka, a northern California city near the quake’s epicenter, described the unusual intensity. “It was an intense jolt. When the shaking stopped, it felt like the house was on rollers. It reminded me of ripples from a stone thrown in water,” he told AFP.
Earthquake History in California
Northern California lies at the junction of several tectonic plates, making earthquakes common. Significant past events include the 1994 Northridge quake in Los Angeles, which caused dozens of deaths, thousands of injuries, and billions in damage. The infamous 1906 San Francisco earthquake, accompanied by a tsunami, claimed over 3,000 lives and caused devastating fires.
While the tsunami warning was eventually lifted, the earthquake served as a reminder of the region’s seismic activity and the need for preparedness.
