A storm system that triggered deadly tornadoes and flooding in the US Midwest and Southwest was pushing north on Tuesday, bringing snow and ice to a swath of the country from Iowa to Massachusetts, and setting up another day of air travel delays.
More than 40 people were killed in wild weather in the United States during the Christmas holiday season, including 11 in the Dallas area who died in a series of twisters that reduced buildings and homes to splinters.
The severe weather also stranded tens of thousands of air passengers during one of busiest travel periods of the year.
By early Tuesday, nearly 600 flights had been cancelled in the United States. About 2,900 flights were cancelled on Monday and nearly 5,000 others delayed according to FlightAware.
The Northeast, which basked under unusually mild temperatures over the Christmas holiday, was getting its first major snow and ice of the season, with significant snowfall in upstate New York and New England. The busy corridor from New York City to Washington DC could expect sleet and rain until midday Tuesday, according to the NWS.
In Chicago, pelted by sleet and strong winds, more than 1,300 flights were cancelled on Monday at O'Hare Airport, a hub for both United Airlines and American Airlines.
On its Twitter account, United tried to reassure passengers that they would be rebooked as soon as possible.