LOS ANGELES, Nov. 26 -- Severe weather including storms, snow and wind chills are forecasted in the United States during the Thanksgiving week, posing challenges to Americans who plan to travel in the "busiest Thanksgiving ever."

Nearly 80 million Americans are expected to travel over Thanksgiving, exceeding pre-pandemic numbers and setting a new record, according to the American Automobile Association.

The U.S. Transportation Security Administration (TSA) expects to screen 18.3 million people at U.S. airports between Tuesday and next Monday, 6 percent more than during the corresponding days last year.

Tuesday and Wednesday are expected to be the busiest air travel days of the seven-day stretch, with 2.8 million and 2.9 million people are projected to travel by air, according to the TSA.

"This will be the busiest Thanksgiving ever in terms of air travel," said TSA Administrator David Pekoske.

Staffing shortages of the U.S. Federal Aviation Administration could slow down air traffic on busy travel week. Millions of travelers hitting the roads or heading for the airport may face delays due to long lines and severe weather.

Two major storm systems may bring travel chaos to much of the country, dumping rain and snow across communities and major cities, according to the U.S. National Weather Service (NWS). About 17,000 flights have been canceled or delayed because of severe weather nationwide since Friday.

Winter storm warnings and advisories are in place across 14 states, with up to 7 feet of snow set to hit some mountain areas.

A snowstorm swirling in Colorado on Tuesday is covering mountain roads with snow and ice, making travel hazardous due to slick conditions.

Roads, especially mountain passes, are quickly deteriorating and will continue to worsen as snow intensifies throughout the day, according to the NWS.

Travel will become difficult to impossible due to snow and blowing snow. Roof damage is possible due to the weight of heavy snow, the NWS said.

In California, a storm warning covers the central part of the state, and roads and especially bridges and overpasses are expected to become slick and hazardous.

The first significant Arctic outbreak of the season will arrive in the northern Rockies and northern Plains on Thanksgiving Day and Friday, according to the NWS.

The cold will advance farther south and east through much of the Plains and Midwest this weekend. Temperatures are likely to be the coldest since mid-late February, according to the NWS.

The weather agency warned travelers to prepare for cold and heavy lake-effect snowfall across portions of the northern United States during Thanksgiving.

  - Xinhua