Earlier in the day, 34 deaths were reported as extreme cold, wind and snow continued through Christmas. 

The snowstorm has settled over an unprecedentedly wide area from the Great Lakes near the US-Canada border to the Rio Grande River along the US border with Mexico.

At least 12 states, namely Colorado, Illinois, Kansas, Kentucky, Michigan, Missouri, Nebraska, New York, Ohio, Oklahoma, Tennessee and Wisconsin reported a total of 50 deaths, NBC News said.

The city of Buffalo in northeastern New York state had the most casualties, with more than a meter of snow falling over the weekend. As of today, at least 14 people had died, the report said.

According to city police, the dead were found "outside and in cars."

New York Governor Kathy Hochul called the natural disaster "the most devastating storm in Buffalo's long story history." 

According to Hochul, 15,000 people in and around the city remain without electricity, and repair work has been delayed until Tuesday.

US media also reported that over 3,100 flights have been canceled and another 7,100 have been delayed across the US, with especially difficult situation reported in Detroit, Chicago, Minneapolis, Denver.