A howling storm across the US north-east left the New York-to-Boston corridor shrouded in up to 3ft of snow, stranding drivers on motorways overnight and piling up drifts so high that some homeowners could not open their doors.
More than 650,000 homes and businesses were left without electricity.
Airlines cancelled more than 5,300 flights. The three major airports serving New York City were allowing some flights to land on Saturday morning. Boston's Logan Airport expected to reopen later. Across the region, flights were expected to be back on close to normal schedules on Sunday.
At least six deaths were blamed on the storm, including three in Canada.
A little more than 11 inches fell in New York, but the city was "in great shape" and "dodged a bullet," Mayor Michael Bloomberg said, predicting streets would be cleared by the end of the day.
Hundreds of drivers abandoned their vehicles on New York's Long Island, and even snow ploughs were getting stuck. Emergency workers used snowmobiles to try to reach stranded motorists, some of whom spent the night stuck in their cars.
Massachusetts, Rhode Island and Connecticut closed roads to all but essential traffic.
Some of the worst of the storm appeared to hit Connecticut where even emergency responders found themselves stuck on highways all night.
Flooding was a concern along the coast, and some homes were evacuated in a couple of Massachusetts communities.
In southern Ontario, an 80-year-old woman collapsed while shovelling her driveway, and two men were killed in car crashes. One pedestrian was struck by a vehicle and killed last night in Connecticut, and a 23-year-old New York man ploughing his driveway with a tractor went off the edge of the road and was killed, police in those states said.