In case you've never heard of a 'firenado' before, it's essentially exactly what it sounds like: a fiery tornado. Except, it's not. In fact, firenados aren't tornadoes at all; they're more like dust devils than anything.
Firenados can occur when a massive outdoor fire breaks out, such as natural wildfires. As the hot air from the flame rises, it can start exhibiting a spin on its way up. Fire embers then begin to ride the breeze upward, creating what looks like a swirling, fiery column.
Another fun fact: firenadoes don't last very long; many of them fizzle out in a matter of minutes while the fire rages on at ground-level.
A firenado can reach temperatures exceeding 2,000º Fahrenheit and stretch hundreds of feet into the air, so it's smart to stay far away from them. As long as you keep your distance, you won't be harmed by a firenado, so feel free to break out the smartphone camera and grab some footage if you're ever lucky enough to film one.