Last night San Francisco Bay was hit with a 4.5 magnitude earthquake. It was felt all over the region. With the USGS said there was a 2% chance of one or more aftershocks larger than magnitude 4.5 over the next week, and as many as four aftershocks of magnitude 3 or higher.

For more info, please read the original article by LA Times:
https://www.latimes.com/california/story/2019-10-14/earthquake-4-7-quake-reported-near-walnut-creek-calif