Airports were shut down and several hundred flights were cancelled on Friday as winter storms swept across the Midwest and northeastern US.
More than 500 flights were cancelled at airports across New York state, and the storm was expected to dump more than 20 centimetres of snow, and later sleet and rain in some areas.
Milwaukee's General Mitchell International Airport was shut down, and areas in southern Wisconsin received about 30 centimetres of snow.
Snow and ice created havoc at major international airports such as O'Hare International in Chicago and New York's John F Kennedy International, where flights were at least three hours late. There were also delays reported in Detroit and Philadelphia, according to the Federal Aviation Administration.
The National Weather Service warned drivers to be prepared for slippery roads and limited visibility. New York Mayor Michael Bloomberg said that the city had 193,000 tonnes of salt ready and 2,000 workers clearing snow from the streets.
Forecasters said that the storm was part of the same weather system that brought snow on Thursday to Las Vegas, causing the lowest temperatures for 20 years in some areas.
The 10 centimetres of snow that fell late Wednesday on Las Vegas' McCarran airport was the second highest total since 1967 and the highest for the month of December since records began in 1937.