Affected airports include O’Hare and Midway in Chicago–where up to a foot of snow is expected–and Kansas City International Airport. Numerous airports outside the region were also impacted by related flight delays and cancellations, including New York City’s LaGuardia and John F. Kennedy, scuttling the plans of tens of thousands of people headed home after the holiday.

Delayed travelers at Chicago O'Hare Airport amid the storm
Delayed travelers at O’Hare.
Image: Kevin J. Delaney/Quartz

Travelers and residents in areas where snow is falling heavily are being advised to be careful in dangerous conditions wrought by the storm, such as reduced visibility, strong winds, and possible power outages.

It’s not clear yet how this will affect carriers financially, but a spate of canceled flights like this typically costs airlines millions of dollars in passenger refunds and other costs associated with rescheduling and rerouting.

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