Depends on where in the Bay Area you were: https://earthquake.usgs.gov/earthquakes/eventpage/nc73799091/shake-alert https://earthquake.usgs.gov/earthquakes/eve

Depends on where in the Bay Area you were: https://earthquake.usgs.gov/earthquakes/eventpage/nc73799091/shake-alert https://earthquake.usgs.gov/earthquakes/eventpage/nc73799091... Santa Clara had 2 seconds of advance warning, and Sunnyvale had 4 seconds. San Francisco got 18 seconds of warning, though was outside the "ground motion" zone.