According to Joe Pedigo, a National Weather Service meteorologist, lower Michigan and parts of New England could get more than 30cm of snow on Monday, as rain fell from the lower Mississippi Valley up through the Ohio Valley.
The bad weather and the need to de-ice aircraft prompted the cancellation of 100 scheduled departures at Dallas-Fort Worth International Airport, an airport spokesman said on Monday morning
More than 400 flights were cancelled there on Sunday.
In Oklahoma, seven of the 15 deaths in the state occurred in one accident in which a minivan carrying 12 Mexican residents slid off an icy road on Sunday and struck an oncoming truck, the Highway Patrol said.
Late on Sunday George Bush, the US president, declared a federal disaster for Oklahoma because of the storm.