And there's no guarantee they'll be able to catch a flight tomorrow, Sunday or even Monday.
Southwest Airlines canceled all flights at Midway International Airport for Friday after a ground stop at Chicago airports earlier in the day. At O'Hare, about 1,500 flights were canceled.
The ground stop was triggered by a fire at an FAA facility in Aurora. It was lifted at 11 a.m., but planes are moving at a "reduced rate." The headaches could continue for travelers for days due to extensive damage at the FAA facility.
"We came in to look at the display. As you see, delayed and canceled. Delayed and canceled. Now it's time to find a car and see if we can get back to where we're going," Stephen Cody, passenger at Midway, said.
At Midway, about 450 flights were canceled on Friday. Southwest Airlines proactively canceled all flights at Chicago Midway International Airport and Milwaukee's General International Airport through "close of business" on Friday.
At O'Hare, the cancellations and delays, which average more than 30 minutes, continue. Many passengers told they would not be able to fly out Friday made other plans.
Many waylaid passengers decided to rent a car instead. They found themselves in good company; travelers told ABC 7 News they could not find car rentals by the evening.
PHOTOS: Fire at regional FAA facility grounds Chicago flights
Airlines are urging travelers to check the status of their flights at www.fly.faa.gov.
Officials said the fire at the FAA facility was intentionally set, but is not considered a terrorist attack.
VIDEO: Fire set at FAA facility, police say