More than 1,370 flights had been canceled as of Tuesday morning, as the third winter storm in two weeks took aim at the Midwest and mid-Atlantic, according to flight-tracking firm FightStats.
Most of the cancellations impacted airports in Chicago and Minneapolis, but delays rippled across the country.
The storm, named Saturn by the Weather Channel and Snowquester by other forecasting outlets, was expected to move east late Tuesday and Wednesday, where its effects will be felt at airports from Cleveland to Washington, Baltimore and Philadelphia.
Major carriers issued flexible rebooking policies for flights to, from or through the airports in the storm's path.