A 6.0 earthquake that centered near South Napa shook Bay Area residents in their beds early Sunday morning. U.S. Geological Survey officials said the earthquake is the largest to hit the Bay Area since the Loma Prieta Earthquake almost 25 years ago.
The temblor was recorded at 3:20 a.m. and was located 6 kilometers northwest of American Canyon, according to the U.S. G. S. It had a depth of 10.8 kilometers. The nearest large city to the epicenter is Vallejo. (View a U.S.G.S. shakemap of the earthquake.)
The U.S.G.S. also reported 2.5 and 3.6 magnitude aftershocks about four miles southwest of Napa at 5:01 a.m. and 5:47 a.m., respectively. Several smaller aftershocks have also been reported.
Officials said 30 to 70 small aftershocks could hit the area during the next week.
Emergency agencies are reporting minor injuries but no deaths have been reported. PG&E is reporting tens of thousands of customers are currently without power across the Bay Area, mainly in Napa and Sonoma counties.
A city spokesman for Napa said firefighters are responding to structure fires, and a number of masonry buildings in downtown Napa have suffered severe damage. He said several stores have broken windows and there are water main breaks in several locations.
Napa also opened an Emergency Operations Center in response, and Vallejo activated its center. Vallejo police are reporting isolated structure damage to downtown buildings and on Mare Island. Police are also reporting water outages from water main breaks, minor roadway damage, minor gas leaks and power outages.
The Palo Alto Police Department said it did not receive any reports of damage or injuries.
The California Highway Patrol is reporting the westbound off-ramp of state Highway 37 and westbound Interstate Highway 80 to state Highway 37 are closed due to possible damage. The CHP is on the scene inspecting the roadways.
Damage has also been discovered on state Highway 121 at state Highway 129 in Napa. Parts of Congress Valley Road and Buhman Avenue have also been closed due to significant road damage, according to the CHP.
There has been no reported damage to roadways in the South Bay, Peninsula and East Bay, according to the CHP. Officers are currently checking roads for obvious damage.
Bridges and roads are remaining open as they are being inspected.
Law enforcement and emergency agencies across the Bay Area are asking residents not to call 911 unless they have an emergency.
California Gov. Edmund Brown Jr. said in a statement Sunday morning the impact of the earthquake is being felt throughout the region.
"My Office of Emergency Services has been on full activation since early this morning and is working close with state and local emergency managers, first responders and transportation officials to respond to impacts to residents and critical infrastructure," he said. "These safety officials are doing all they can to help residents and those living in affected areas should follow their guidance and instruction."
Read this U.S.G.S. tectonic summary for more detail about the origin and location of Sunday's earthquake..