CHICAGO (AP) — Nearly 500 flights have been cancelled on one of the busiest travel days of the year as a fast-moving winter storm bears down on much of the Midwest on the last day of the Thanksgiving holiday weekend.

The flight-tracking website FlightAware reported that 491 flights headed to or from the U.S. had been cancelled as of 11 a.m. Sunday.

The site reported that the majority of the cancellations are flights that were supposed to be routed through Chicago or Kansas City — two areas forecast to be hit hard by the storm.

The National Weather Service has issued a blizzard warning for parts of Nebraska, Kansas, Missouri and Iowa. Other parts of central plains and Great Lakes region are under a winter storm warning.

(© Copyright 2018 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)