So far, there are 20 delays and 70 cancellations at Bush, according to the Flight Aware website.
About 4 million people are expected to travel by air for the Fourth of July, according to AAA.
As for what's causing the delays and problems with flights, it's a combination of weather and staffing shortages at the airlines and with air traffic control.
It may take some time for flights to get back on track.
ABC13 spoke to some passengers, but it seemed like some of them planned for the worst and got to the airport early.
"I had a feeling it was going to be packed, so come early," one woman traveling said.
If you plan on parking at the airport, remember you can make a reservation online. At last check, all three garages at Bush Airport were about 85% full.
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