USA TODAY's tracker showed 500,000 households without power at 9 a.m. Saturday. Nearly 185,000 Michigan customers were affected by the largest outages.
More than 90,000 Wisconsin customers lost power Saturday morning, mostly around Milwaukee. Tens of thousands in Vermont and New Hampshire were also without power.
Utah and Wyoming may get "impressive snowfall" this weekend, according to the Salt Lake City National Weather Service. Winter storm warnings cover northern Utah and southwest Wyoming for up to four feet of snow.
The winter storm that caused blizzard warnings in the Great Lakes and Upper Midwest on Friday is expected to travel northeast on Saturday, bringing snowfall rates of up to 2 inches per hour.
Forecasters warned of blizzards and power outages. The National Weather Service predicts coastal and river flooding in the Northeast and Mid-Atlantic on Saturday due to heavy rain.
The weather service expects lake-effect snow to last through midweek, with whiteout conditions. The storm's snow production will decrease Saturday. The weather office warned Saturday that parts of the South could get wintry weather by Sunday. The meteorological service predicts "likely to develop" snow, sleet, and freezing rain in eastern Oklahoma, northeast Texas, Louisiana, Arkansas, and much of Tennessee.
Arctic air will drop from Western Canada and sweep throughout the Northwest and Northern Plains early next week after this weekend's storm. Multiple record-cold temperatures are predicted by the weather service.
From the northern Rockies to Kansas and Iowa, wind chills will drop to -30 degrees. Frozen skin and hypothermia are possible in Montana and the western Dakotas at negative-50 degrees.