The Slide Fire is not only a problem for the people living in the high country but also for those trying to visit or leave it.
US Airways said heavy smoke hanging over Flagstaff forced the airline to cancel nine flights Wednesday, affecting hundreds of travelers.
High winds have been blowing smoke and ash into the area, dangerously reducing visibility.
US Airways said they were back operating flights to and from Phoenix and Flagstaff on Thursday. There were a few delays unrelated to the Slide Fire.
US Airways canceled four flights from Phoenix to Flagstaff on Wednesday, and another five headed to Phoenix.
NAU student Kaleigh Emery was one of many passengers who had to find another way to get home.
"I just heard from the people at the gate that the flight was canceled due to all of the smoke and that it was too dangerous," she said. "And, pretty much, if the flight was to go out, it would just turn around and come back. It scares me to go back and see what the damage has done and how bad the smoke actually is."
US Airways has 12 flights scheduled, between Phoenix and Flagstaff, on Thursday.
But if smoke from the Slide Fire continues to be a problem, those flights could be canceled, too.
"Safety is our first priority for our customers and crew, and we are evaluating the situation in Northern Arizona," the airline said in a statement Wednesday night.
If you've booked one of those flights, check the status ahead of time.
You can do that by calling US Airways' reservation line at 1-800-428-4322 or visiting the airline's website.
Stay with cbs5az.com and CBS 5 News for updates on this developing story.
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