Weather Words: Crown Fire

As if fighting wildfires aren’t challenging enough, crown fires can make it even more challenging. Crown fires advance from the tops of the trees or shrubs, independent of the ground fire. Many times a wildfire will start on the forest floor, then as the flames grow in height they ignite the canopy, then a crown fire races on.

Crown fires are sometimes too high in the trees for firefighters to reach, so they oftentimes have to be fought from above with aircraft. They are also very dangerous for firefighters because branches from the burning trees above can fall on firefighters below.

High winds can carry crown fires large distances over a very short amount of time. They jump from tree to tree, feeding on the dry needles and vegetation. Their embers can get lofted in the air by the wind and carried several miles away before igniting another fire, known as spot fires. These spot fires are difficult to predict and make fighting wildfires even more challenging.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.