The Arctic blast winter storm that lashed across the US over the last two days has so far claimed 34 lives, with the city of Buffalo, in New York state, being the worst hit.
The deep freeze that gripped most of the nation, along with snow, ice and howling winds, caused power outages and trapped people inside their cars.
In Buffalo, the blizzard left the city marooned as emergency services struggled to reach high-impact areas.
The National Weather Service said 43 inches of snow fell on Buffalo on Sunday morning.
The snowfall and blizzard conditions halted traffic, froze power substations and left at least 12 people dead, according to Erie County officials.
While three deaths were reported overnight in the Buffalo region, some victims were found in cars and some in snow banks. There are fears that the death tally might rise further.
Over 55 million people continue to remain under wind chill alerts and freeze warnings are in effect across the South.
Besides, the cities in the Southeast, Midwest and East Coast also experienced the aftermath of the winter storm as they recorded their coldest Christmas in decades.
Florida had the coldest December 25 since 1983 for Miami, Tampa, Orlando and West Palm Beach.
New York City also saw record-cold temperatures on Christmas Eve at several locations, including its JFK and LaGuardia airports.
Power outages
Over 150,000 U.S. homes and businesses were without power on Sunday, according to PowerOutage.us. In Buffalo, 16% of residents had no electricity on Sunday.
A power grid operator supplying electricity for at least 13 states in the east has asked the customers to conserve power and set thermostats lower than usual on Christmas day too because usage was straining capacity.
The situation prompted the US Department of Energy to declare an emergency Friday in Texas.
Due to the harsh weather conditions, flights continued to be cancelled on Sunday. On Christmas Day, 1,350 were cancelled while over 3,400 flights were cancelled Saturday
The effects of the blizzard extended to Canada too as the provinces of Ontario and Quebec bore the brunt of the storm.
In Quebec, almost 120,000 customers were without electricity on Sunday. Officials say it could take days for some households to be reconnected, reported BBC News.