US President Joe Biden approved a state of emergency for New York as search-and-rescue operations continued in the state following a major snowstorm.
The storm has left nearly 50 people dead, including 28 in the state of New York.
Buffalo, a city close to the border with Canada, faced particularly ferocious conditions throughout the weekend.
Speaking to reporters on Monday, New York Governor Kathy Hochul said some areas in the western part of the state had received up to one metre of snowfall overnight.
And an additional 23cm of snow were expected to fall in western New York on Tuesday, the National Weather Service said, as workers continued to dig out snowfall that has blanketed the region.
Ms Hochul said more than 550 rescues have been conducted since the storm began.
Erie County executive Mark Poloncarz on Tuesday morning said the entire county remains under a state of emergency and that driving bans are still in place for Buffalo and Lackawanna.
Rising temperatures are forecasted for later in the week, though that could bring some flooding to the region.
About 1.7 million people were without power in the frigid conditions but that number had been greatly reduced by Tuesday morning.
Ms Hochul warned residents to stay off the roads.
“The storm is weakening, but we are not out of the woods yet,” she said.
Buffalo Niagara International Airport will remain closed through Wednesday morning, at one point accumulating up to 1.25 metres of snowfall.
Ms Hochul announced on Monday night that the White House had authorised her request for a federal emergency declaration, which authorises agencies to provide assistance to New York.
US winter storm kills dozens
The White House said Mr Biden had directed his administration to immediately respond to Ms Hochul's requests for federal assistance.
Mr Biden also “shared that his and the first lady's prayers are with the people of New York and all those who lost loved ones”, the White House said in a readout of his call with Ms Hochul.
Mr Poloncarz tweeted that Erie County had 27 confirmed storm-related deaths, including 14 people who were found outside.
The winter storm brought below-freezing temperatures across the entire US mainland at the weekend.
“It is the blizzard of the century,” Ms Hochul said during a news conference.
And parts of the US were expected to face another storm this week.
Some western US states were expected to experience high winds, heavy rain and snow, while Utah and Wyoming were forecast to experience at least one winter weather system into Tuesday evening.
Colorado is also likely to close the year with heavy snowfall.
The storm, which brought misery to thousands of American passengers before the holidays, continued to disrupt travel after Christmas Day.
About 2,900 flights were cancelled in the US on Tuesday, data from FlightAware showed.
Southwest Airlines was forced to cancel more than 2,500 — or 62 per cent — of its flights.
Its US competitors — American, United, Delta and JetBlue — in contrast experienced cancellation rates between 0 and 2 per cent on Tuesday.
The discrepancy of cancellation rates between Southwest and its competitors prompted scrutiny from the US Department of Transportation.
The agency expressed its concern over the airline's “unacceptable rate of cancellations and delays”, and added that it was investigating whether the airline was providing support to stranded customers.
Southwest said “continuing challenges” from the winter storm are affecting its customers and employees “in a significant way that is unacceptable”.
“We recognise falling short and sincerely apologise,” Southwest said in a statement.
