Nov 9, 2021
A weak to moderate atmospheric river event impacted the SF Bay Area November 8th and November 9th, bringing moderate to locally heavy rain and gusty winds. A low pressure system from the Gulf of Alaska deepened over the NE Pacific and made landfall in the OR/WA area November 8th. This system tapped into subtropical moisture from the Pacific Ocean and dropped substantial rainfall over the North Bay and into the immediate Bay Area, with accumulations up to 4 inches in coastal North Bay. A strong l
Source: NOAA National Weather Service Storm Events Database (event 992219). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Alameda County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.