SACRAMENTO, CALIF. ? A drenching winter storm swelled rivers in northern California to their highest levels in seven years, causing power outages and forcing some residents to evacuate.

Flood warnings were in effect for the northern half of the state after the storm swept through Tuesday and Wednesday. One person was killed in a car crash caused by a mudslide.

“It’s been several years since we’ve had this widespread of flooding, and we’re not done,” said Rob Hartman, of the National Weather Service’s California-Nevada River Forecast Center in Sacramento.

The last significant flooding in the region was during the El Niño year of 1998 and a year earlier, when three people died after levees collapsed north of Sacramento. The danger is lower this time because there is relatively little snow in the Sierra Nevada to be melted by the warm rains, officials said.

In Modesto, a mudslide led to a pileup that killed a motorist Monday. And in Mendocino County, four homes were evacuated after a landslide Tuesday night.

Rivers were cresting from the Napa County wine country to the far northern coast, including the Russian, Navarro, Scott, Klamath and Eel rivers. They were expected to rise to flood stage periodically through the weekend.

More storms were forecast for Friday through the New Year’s weekend. The system was expected to spread farther south by Saturday and potentially cause mudslides and flash floods in recently burned areas of Southern California.