How Wildfires Can Create Their Own Weather

This year has seen a brutally hot, dry summer in the Western U.S., with hundreds of heat records broken amid an unprecedented drought that has created a tinderbox for ferocious wildfires.

Weather often contributes to the growth and spread of wildfires, and high heat, low humidity, gusty winds and lack of rainfall are among the prime culprits. But fires also can influence the weather.

Sometimes, wildfires can create a witches’ brew of weather, including pyrocumulus clouds, thunderstorms, dry lightning and even fire tornadoes.

Here’s a look at some of the types of weather that wildfires can create: Pyrocumulus clouds – aka fire clouds – look like giant, dirty-colored thunderheads that sit atop a massive column of smoke from a wildfire.

Here’s how it happens: When air over the fire becomes superheated, it rises in a large column. As air with more moisture rises, it rushes up the smoke column into the atmosphere, and the moisture condenses into droplets. That’s what creates the ‘fire clouds’ that look much like the thunderheads seen before a big thunderstorm.