USGS initially estimated more than 150,000 people might have been exposed to earthquake shaking, between just north of Fort Bragg to Eureka. One USA TODAY reporter in San Francisco did not feel its impacts, but another resident right on the San Francisco Bay said it was the longest earthquake she'd ever felt.

According to the US Geological Survey, the quake struck around 10:44 a.m., west of Petrolia, California in the Pacific Ocean. A Tsunami Warning has been issued for 45 miles southwest of Eureka. The earthquake was first preliminarily registered as having a magnitude of 6.6, but USGS updated it a 7.0.