Schools canceled or delayed classes from New York to Maine as highways turned slippery and wind gusted to 40 mph (64 kph) in parts of the region.
The speed limit on part of the Massachusetts Turnpike was cut to 40 mph (64 kph) as police reported numerous traffic accidents around the state during the morning commute.
Most courts in Maine closed for the day and Gov. John Baldacci considered sending state workers home early.
"It's snowing so hard you can hardly keep your eyes open," said Bill Swain, spokesman for Maine's Sugarloaf USA ski area in Carrabassett Valley.
The National Weather Service said a foot (1/3 of a meter) of snow was possible in the mountains of northern New England, with the potential for 20 inches (51 centimeters) in northern Maine. Upstate New York's central Adirondacks and Lake George region could see 12 inches (30.5 centimeters) of snow.
By Monday morning, 6 inches (15 centimeters) of snow had fallen at Springfield, Vermont, and in parts of central New York state.
Ice storm warnings were issued for Massachusetts and Connecticut, while winter storm warnings were in effect in Massachusetts, Vermont, New Hampshire, Maine and northern and western New York.
Air travel was disrupted Monday at the Portland International Jetport in Maine as flights were canceled because of poor conditions at connecting airports.
Hundreds of flights into the New York City area's three main airports - Kennedy, Newark Liberty and LaGuardia - were delayed as long as two hours Sunday because of wind and ice, but no delays were reported early Monday.
Ice caused a JetBlue plane to slide off the runway at Syracuse's Hancock Airport late Sunday. No one was hurt, but it took crews two hours to free the stuck plane.
The storm dumped snow and ice from the Plains across the Upper Midwest on Saturday.
Lingering rain and poor visibility caused about 50 flight cancelations Sunday afternoon at Chicago's O'Hare International Airport , forcing about 75 people to stay at the airport overnight, said Gregg Cunningham, a spokesman for Chicago's Department of Aviation.
The weather was blamed for four deaths in Michigan, three in Wisconsin, and one each in Illinois, Indiana, New Jersey, New York, North Dakota and Colorado.
While the Midwest dug out and the Northeast braced itself, a separate storm raked the Oregon and Washington coasts with winds gusting higher than 100 mph (160 kph) in some spots. Officials warned of coastal flooding.