Airlines canceled more than 2,000 flights in the Midwest on Wednesday as a blast of what federal forecasters called "dangerous" cold snarled operations.
Temperatures will remain well below zero degrees Fahrenheit in the Chicago area on Wednesday and early Thursday with "dangerously cold wind chills" of as low as minus 50 that can cause frostbite to exposed skin within five minutes, the National Weather Service said.
Airlines canceled more than 1,450 flights in and out of Chicago's O'Hare International Airport scheduled for Wednesday, more than half of the day's schedule at the American Airlines and United Airlines hub, according to flight-tracking site Flightaware.com. More than 330 flights were canceled at nearby Chicago Midway Airport, about two-thirds of its schedule.
American said "extreme temperatures" and a winter storm that hit the Northeast on Tuesday evening, prompted it to cancel 675 Wednesday flights, including 270 departures from O'Hare.
Delta Air Lines, American, United, Spirit Airlines and JetBlue Airways said they would waive date-change fees for travelers affected by the severe weather. Southwest Airlines, which doesn't have date-change fees, said it wouldn't charge travelers booked in and out of more than two dozen U.S. airports the fare difference to fly at a later date due to the extreme weather. Southwest canceled 675 flights on Wednesday, 16 percent of its daily operation, according to Flightaware.com.
While aircraft can take generally take off in low temperatures, the bitter cold limits how long ground workers can remain loading baggage or servicing aircraft.
Delta, which operates hubs in Minneapolis and Detroit, is preparing for the frigid conditions by increasing staffing of ground workers more employees can take more frequent breaks indoors, as well as moving some aircraft into heated hangars overnight, said spokesman Michael Thomas.
The cold follows strong winter storms that brought snow and heavy rain across a broad swath of the U.S. Some 300 flights in and out of Hartsfield-Jackson Atlanta International Airport, Delta's home hub and the world's busiest airport, were canceled on Tuesday.