JACKSONVILLE, Fla. – Wildfires don’t just burn. When they get intense enough, they can generate their own weather. We’re talking tornadoes, powerful wind systems, and even thunderstorms.
Meteorologist Jenese Harris breaks down the science behind how it happens.
Fire tornadoes are a real threat
A fire tornado may sound far-fetched, but it is possible. According to Harris, this phenomenon typically occurs when extreme wind speeds combine with intense heat and unpredictable fire behavior. When winds begin to spin, they pull air inward and rotate debris — similar to a conventional tornado. In a wildfire scenario, that spinning motion can rapidly spread flames in new directions.
How embers jump highways and start new fires
Fire can also appear to “jump” — sometimes across major roadways. Intense fires create powerful updrafts that carry burning embers high into the air. Wind then transports those embers far ahead of the main fire, where they can land in new fuel sources and ignite what are known as spot fires.
That’s exactly what happened during the 1998 fire, when wildfires jumped Interstate 95 as embers flew through the air amid sustained winds of 25 to 30 miles per hour.
The science of pyroconvection
Wildfires can also produce weather systems similar to convection storms — a process called pyroconvection.
Think of it like a pot of boiling water: the fire releases intense heat, and heat rises. That upward motion — called an updraft — draws in cooler surrounding air, mimicking the dynamics of a convective storm. As that rising air reaches higher altitudes, it cools and condenses, forming what are known as pyrocumulus clouds. From those clouds, full thunderstorms can develop.
Why that rain isn’t welcome
While rain might seem like a relief during a wildfire, the thunderstorms that form from pyroconvection bring a dangerous side effect: lightning. Those lightning strikes can ignite new wildfires, compounding an already dangerous situation.