Two massive wildfires in Arizona and Utah are burning so intensely they’ve formed dangerous “fire clouds” that create their own erratic weather.

The Dragon Bravo Fire on the North Rim of the Grand Canyon has become a “megafire,” burning over 164 square miles and destroying the historic Grand Canyon Lodge. In Utah, the Monroe Canyon Fire has scorched 75 square miles, forced evacuations, and knocked out power.

Both fires have produced towering pyrocumulus clouds—some reaching 25,000 feet—that can trigger unpredictable winds, posing risks to firefighters, The Guardian has reported.

Experts warn these extreme fire behaviors may increase with climate change.

Written by B.C. Begley