More than 2,000 flights canceled as 'deadly' polar vortex hits the US

Airlines across the country have already canceled more than 2,000 flights as “historic low” temperatures continue to blast the Midwest.

According to the National Weather Service, temperatures will remain well below zero degrees Fahrenheit in the Chicago area on Wednesday through early Thursday.

“A record arctic air mass will remain over the central and eastern U.S. over the next several days. Wind chill values of 30 to 60 degrees below zero will be common across the northern Plains, Great Lakes, and upper Midwest,” NWS said in a tweet.

According to flight-tracking site, of those 2,000 cancelations, more than 1,000 are flights in and out of Chicago's O'Hare International Airport, while 330 were canceled at nearby Chicago Midway International Airport--which equates to about two-thirds of its schedule.

American Airlines said it had to cancel more than 400 flights this week due to "extreme temperatures."

Other major airlines, including Delta, United and JetBlue, all announced they would change fees for travelers affected by the weather.

Amtrak has also canceled all trains to and from Chicago on Wednesday due to the weather.

According to NWS, the winter blast has already killed at least five people.