To summarize:
A 6.0-magnitude earthquake epicentered at the southern edge of Napa struck at 3:20 a.m.
Damage is reported in the city of Napa ranging from the collapse of commercial building facades in downtown Napa to extensive exterior and interior damage of single-story homes in the surrounding area.
Witnesses are reporting two major fires at the northern end of Napa, one possibly in a mobile home park.
PG&E reports thousands of homes are without power in Napa and Sonoma counties and Vallejo in Solano County.
The California Highway Patrol and Caltrans are assessing damage to roads in the North Bay. Numerous pictures of buckled roads have appeared on Twitter
NBC reporter says it is a fault line that has been dormant for 1.6 million years.
David Schwarz of USGS wonders where the reporter came up with that. Says it was NOT the Franklin Fault.
Reporter says there have been at least 15 aftershocks and more expected.
Schwarz - 50+% probability of a 5.0 aftershock within 7 days.