The harsh conditions come at a busy time for travel.
Flight disruptions began Wednesday, with more than 3,800 U.S. flights delayed and 861 canceled, according to FlightAware.
The Federal Aviation Administration said delays are possible at U.S. airports, including Denver, Salt Lake City, Las Vegas, Minneapolis, Tampa Bay, Los Angeles, Dallas, Boston and Seattle. There was also a delay on the ground at Newark Liberty Airport in New Jersey due to staff shortages.
The US Transportation Security Administration (TSA) claims that the number of passengers during this year’s Thanksgiving Day has already reached a record level.
The busiest days are expected to be the Tuesday and Wednesday before Thanksgiving, as well as the Sunday after the holiday. The TSA expects to screen nearly nine million people at airports over the three days.
Meanwhile, a record number of nearly 80 million Americans are expected to drive at least 50 miles (80 km) per week, according to insurance company AAA. The expected increase is due to gasoline prices being lower than they were during the Thanksgiving holiday last year.