"A lot of people don't think about it outside right now," Rusty Lowe said.
Lowe, with the Hoover Fire Department, says your car and what you flick out of it can serve the same purpose as an open flame.
"A cigarette, maybe some type of mechanical issue with brakes or tires on a car...or just the heat," Lowe said.
They're all factors.
Add that with low humidity, dry conditions, wind and trying to keep warm...it's an easy recipe for devastation.
"Only a spark or something pretty warm," Lowe said. "Gets close to some grass or some wood, or leaves, or whatever, it's pretty easy to ignite."
In the last four days, Hoover Fire has seen at least three of these fires. One was Saturday night off Shades Crest Road, which burned three acres and was believed to have been started by a bon fire.
Then, Monday, off Green Springs Highway, smoke caused visibility to be cut down drastically beside I-65.
"Think about what you're doing right now," Lowe said. "Because it really could cause a catastrophe."
Lowe says the best thing you can do is use common sense both in and out of the car.
"Don't do any burning outside," he said. "It's illegal anyway, but we know some people are going to try to burn their leaves. Now's not a good time to do it."