A 6.1 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 San Mateo County Office of Emergency Services said at 4:30 a.m. that no damage had been reported in San Mateo County.
The city of Napa reported this morning that dozens of people were injured, three critically, and several historic buildings were damaged in the earthquake that struck around 3:20 a.m. about three miles northwest of American Canyon.
Napa city officials said the damaged buildings include the Napa County Courthouse, Goodman Library and Sam Kee Library.
At least two commercial buildings were severely damaged in the quake, which also caused a fire that burned multiple mobile homes on Orchard Avenue in north Napa, city officials said.
There were approximately 50 gas line breaks and 30 water main breaks reported following the earthquake, causing some areas to have low or no water service.
The American Red Cross has set up an evacuation center at the Napa High School gymnasium at 2475 Jefferson St.
The USGS said the quake had a depth of 10.8 kilometers. The nearest large city to the epicenter is Vallejo. (View a USGS shakemap of the earthquake.)
The USGS 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.
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 city of Vallejo reports state Highway 37 at Sonoma has reopened following roadway inspections. Interstate Highway 80 at state Highway 37 is also open in all directions, according to the California Highway Patrol.
Damage has been discovered on state Highway 121 at state Highway 129 in Napa.
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.
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 USGS tectonic summary for more detail about the origin and location of Sunday's earthquake.