More than 300 flights were canceled and a ground stop was initiated at Chicago's O'Hare International Airport Monday evening as thunderstorms capable of producing a tornado headed toward the area.
According to the CDA website, a total of 333 flights had been canceled at O'Hare as of 10:33 p.m., with delays averaging 24 minutes. Arrival delays were averaging 30 minutes, while delays for departing flights were said to be less than 15 minutes.
A total of 506 flights experienced delays of at least 45 minutes within a recent 24-hour span.
A ground stop was also issued at O'Hare due to the severe weather threat, according to the Chicago Department of Aviation. During the ground stop, the FAA took precautions to shelter tower operations staff in place for a short period of time, the CDA added.
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A total of 26 flights were canceled at Midway International Airport, with passengers seeing an average delay of 19 minutes.
Check back for updates on this developing story.