At least five people have died in severe rain and snowstorms that blanketed parts of California with at least five feet of snow in the Sierra Nevada mountains this week, besides triggering flooding and mudslides, officials said.
Forecasters expect the bitter weather to push eastwards into the Rockies and US Midwest through the weekend, while the California Highway Patrol said rain-slicked highways led to two fatal accidents that killed four people.
A family of three, including a one-year-old baby, died in El Dorado County on Tuesday, after their car spun across a rain-soaked freeway to hit another car, the San Francisco Chronicle said.
Another man died in a storm-related car wreck on Wednesday in Napa County, highway patrol dispatchers said, but no further details were immediately available.
One man in Oakland was killed after being struck by a tree, uprooted by the wind and rain, that fell on a homeless encampment, media said
High winds could topple more trees as the soil gets wetter and more saturated, the National Weather Service warned.
Police in Los Angeles and Santa Barbara counties ordered evacuations on Tuesday from areas damaged by last year's wildfires because of the risk that heavy rain could trigger mud and debris flows on charred hillsides.
The snow and rain were brought by a one-two punch of weather, after one Pacific storm hit California on Monday and a second, larger storm arrived on Wednesday, forecasters said.
Both are expected to sweep back-to-back through the Rockies and Midwest, gathering more strength from moisture from the Gulf of Mexico, forecasters said, before hitting the Ohio Valley and the Northeast early next week.
Significant road closures and travel delays remain likely in the Los Angeles area through Friday as storm remnants linger, said Marc Chenard, a forecaster with the NWS' Weather Prediction Center in College Park, Maryland.
The risk of flash flooding and rockslides persists, he said.
"Some areas in the Sierras will get another 5 inches of rain after the 3 inches that already fell, with significant snow fall above 6,000 feet."
The weather is a boon for farmers and ski areas, however, as most of California is recovering from years of drought, the United States Drought Monitor said.