‘Onslaught’ of Atmospheric Rivers Could Soak Northern California Ahead of Christmas

Northern California is bracing for a prolonged stretch of wet weather as multiple atmospheric rivers line up to impact the West Coast over the next week and beyond. Forecasters say the pattern could bring rounds of heavy rain, strong winds, and significant mountain snow—raising concerns about flooding, landslides, and travel disruptions as the holiday period approaches.

“California is looking at historic precipitation from onslaught of atmospheric rivers in next 10-days,” said former National Oceanic and Atmospheric Administration (NOAA) chief scientist and meteorologist Ryan Maue on X. “Could be 20″ or 30” mostly rain in the Sierra from “firehose of moisture” directed right at coast with strong jet stream. This going to be really bad.”

After last week’s storms caused flooding farther north in Washington, the storm track is now shifting south. Meteorologists expect the first wave to deliver rain and gusty conditions to far Northern California beginning midweek, with showers tapering temporarily before the next system arrives.

Another powerful atmospheric river is forecast to push inland late this week, spreading rain and snow across Oregon and eventually into Northern California by Friday. Conditions could worsen over the weekend, when some of the heaviest precipitation is expected to fall, particularly along the North Coast and in the Siskiyou Mountains. Some coastal and mountain areas could see several inches of rain in a short period of time.

Forecasters warn that this kind of sustained moisture increases the risk of flash flooding and debris flows, especially in burn-scarred landscapes. Rivers in the Pacific Northwest that are already running high may also rise again as additional rain moves through the region.

Looking ahead, weather models suggest the stormy pattern may persist into next week, potentially peaking just before Christmas. The National Weather Service has cautioned that atmospheric rivers could create hazardous travel conditions across the West, both on highways and at higher elevations where heavy snow is expected.

Residents and travelers are urged to monitor forecasts closely, allow extra travel time, and be prepared for rapidly changing conditions as this active weather pattern unfolds.