Winter storms have been overwhelming most of the country — one region at a time.

Earlier this week, heavy snow walloped a swath of northern states, impacting South Dakota, Minnesota, Wisconsin, and Michigan. In the Northeast, upstate New York and central Vermont saw between 6-12 inches of snow.

More than 873,000 households in the U.S. were without power as of Friday afternoon, largely in Michigan, California, Illinois and New York, according to utility companies' reports tracked by PowerOutage.us.

As parts of the upper Midwest and Northeast continue to recover from the winter storm system, people in California have begun to brace themselves for severe thunderstorms, heavy snow and potential flooding that will last through Saturday.

Just as noteworthy were the unusual warm temperatures seen in Southern and Mid-Atlantic states, the National Weather Service said. On Thursday, both Nashville, Tenn., and Richmond, Va., saw temperatures hit 85 and 83 degrees respectively.

A rare, slow-moving winter storm looms for California

Parts of Southern California likely will see an intense brew of rain, snow and winds that may cause flooding, according to the National Weather Service.

On Friday, forecasters also urged mariners near the coast of the state's San Luis Obispo and Santa Barbara counties to "seek safe harbor immediately" — warning of severe thunderstorms that could produce sudden waterspouts, powerful enough to "easily overturn boats." The two counties are also at risk of seeing small tornadoes on land.

Meanwhile parts of northern California, including the Bay Area, already have begun to see some snow and gusty winds — leading to road closures, downed trees and power outages.

San Jose, Napa and other parts of the region have been issued a freeze warning for Friday evening through Saturday morning. The sub-freezing conditions will be especially dangerous to unsheltered populations, crops and unprotected outdoor plumbing.

Several school districts in northwest California were closed Friday.

Michigan's brutal snow storm winds down

The storm that pummeled the upper Midwest earlier this week appears to be wrapping up.

Michigan in particular was hit with freezing rain and ice that disrupted travel and was risky for livestock and infrastructure. Port Austin and Midland saw the most snow, with 8 inches and 8.9 inches respectively. Meanwhile southern portions of the state saw high accumulations of ice, according to the National Weather Service.

More than 725,000 households — largely in south Michigan — remain without power as of Friday afternoon.

There is still a chance of more light snow in some parts of southeast Michigan. Meanwhile, across the state, temperatures will be below freezing on Friday. Forecasters expect the weather to warm up by Sunday.

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