Airlines were canceling flights and waiving changes fees Friday as a winter storm brought heavy snow to airports in the Midwest and Great Lakes.

Nationwide, more than 1,700 flights had been canceled and another 4,400 delayed as of 9:50 p.m. ET, according to flight-tracking service FlightAware.

The bulk of the cancellations were concentrated at three airports: Chicago O’Hare, Chicago Midway and Detroit. O’Hare is a major hub for both American and United while Midway is one of the busiest bases for Southwest. Detroit is a busy hub for Delta.

Southwest had canceled its entire Friday morning schedule at both Midway and Detroit, but said it hoped to resume flights at noon local time at each airport.

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Travelers checking in at Tokyo's Narita Airport got this warning for flights bound to Chicago on Feb. 9, 2018.
Billy Axelord, special to USA TODAY

Beyond Chicago and Detroit, other notable airports seeing a weather-related spike in cancellations were Milwaukee and Grand Rapids, Mich. In Canada, the same storm was snarling flights at Toronto Pearson – that nation’s busiest air hub.      

Most big carriers were waiving change fees for customers ticketed to fly to the region during the storm. Details varied by airline, but they generally allowed fliers to make one change to their itineraries without paying change fees or recalculated fares. Airports included in the waivers also varied by carrier, but they covered a spread of destinations from Iowa and Minnesota east through western New York state and Ontario. 

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In the U.S., nearly all of Friday’s cancellations were made preemptively on Thursday as airlines tried to get ahead of the storm. Still, the tally of delayed and canceled flights could grow Friday as snow continues to fall across the region.  

Scroll down for links to the winter-weather waivers currently in place at big North American carriers:

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Air Canada

Alaska Airlines

American

Delta

JetBlue

Frontier

Southwest

Spirit

United

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