The storm has been the first big test for New York City's new Mayor Bill de Blasio, who only took up his job Wednesday.
"If you want safe, clear streets, stay home," he said Friday.
Thousands of domestic and international flights have been cancelled or delayed in several US cities including at New York's John F. Kennedy Airport and in Chicago, Boston and Philadelphia, while thousands of miles of roads were also affected.
Added to the mix was a flood alert for much of Massachusetts' Atlantic coastline.
On Friday, a worker was killed when he was crushed by a 100-foot (30-meter) pile of salt being prepared to treat roads in the Philadelphia area, media reports said.
A 71-year-old woman suffering from Alzheimer's disease froze to death after walking out into the cold and getting lost in northern New York state, authorities said.
At least nine other deaths were blamed on the storm, named Hercules.
Eastern Canada has also been badly hit, and residents in many parts of Newfoundland lost power on Saturday morning, local media reported.
Temperatures there had plunged to minus 15 degrees Celsius, but the wind chill made it feel as cold as minus 35, the reports said.
The bracing weather was also set to impact Sunday's crucial National Football League play-off between the Green Bay Packers and the San Francisco 49ers.
Some media speculated that the eagerly anticipated clash at Lambeau Field in Green Bay, Wisconsin, might be the coldest NFL game in history as freezing temperatures and blustery winds threatened a wind-chill factor as low as minus 35F.
The Packers say they will help fans battle the big freeze at the open-air stadium by handing out free coffee and hot chocolate.