Deaths have been reported in New York, Tennessee, Louisiana, Massachusetts, Kansas and Texas, where a 16-year-old girl was killed in a sledding accident
More than 10,000 flights have been cancelled and schools and roads across the country closed - our map shows the extent of snowfall over the weekend
Freezing rain brought dangerous travel conditions, with sub-zero temperatures on Monday morning - even on the Gulf coast, writes our lead weather presenter
Warnings from the National Weather Service (NWS) stretch from Texas in the south to New England in the north-east
Meanwhile in Canada, Toronto Pearson Airport saw a record-breaking 46cm of snowfall on Sunday - it's the airport's snowiest month since records began
The number of flights cancelled today has now increased to 10,061, according to website FlightAware.
New York has taken the brunt of the disruption, with 379 flights cancelled and more than 30 delayed across JFK, LaGuardia and Newark airports.
The winter storm is also contributing to widespread cancellations at Boston Logan International as well as Washington's Dullies, Reagan and Baltimore airports.
And across the border, Toronto's Pearson Airport is also experiencing disruption - with multiple domestic and international flights delayed or cancelled.
The winter storm has exited the mid-south but "extremely cold wind chills have taken its place", the US National Weather Service in Memphis, Tennessee, says in an update.
It's warning that early morning wind chills in much of the area will be "well below" 0F (-17.8C).
