LATEST TIMELINE: Atmospheric river to hit Bay Area this week, bringing heavy rain and flooding to parts
"Rainfall chances increase beginning Wednesday and last into the weekend as a rather impressive system sets up," the weather service said.
Should the atmospheric river hit, the northern portions of the North Bay would likely take the brunt of the atmospheric river, according to the weather service, but those impacts could shift slightly southward closer to the SF Bay.
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Cities on the North Coast could be pelted with over 10 inches of rain, while San Francisco and Oakland might get one to four inches, according to the National Oceanic and Atmospheric Administration weather prediction webpage.
Many Bay Area residents will recall as just one example the atmospheric river of early 2019. It sent heavy rain and gusty wind through the Bay Area, causing flooding, downed trees and other problems. Thousands of utility customers lost power as trees and other debris fell on power lines and airports cancelled or delayed flights.
An atmospheric river, as the name suggests, is like a river of water vapor in the sky flowing from the tropics to higher latitudes, often bringing a huge amount of rain, according to the National Oceanic and Atmospheric Administration.