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Lone Star Fire

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Yellowstone National Park
National Park Service

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Weather's Influence on Fire Behavior

Lone Star Fire Wildfire
News – 8/29/2020

Fire managers choose between a variety of strategies when suppressing wildfires. While managing fires can be complicated and challenging, the basic principles of fire are relatively simple. Fire needs three elements to ignite and continue to burn: oxygen, heat, and fuel. This is referred to as the fire triangle

Just like there is a fire triangle, there is another triangle for the factors that have the greatest influence on how the fire behaves once it ignites. Those factors, making up the fire behavior triangle, are weather, topography, and fuels.

Weather is perhaps the most variable factor in the fire behavior triangle, and it can quickly change. Fire teams closely monitor forecasts, noting the expected wind speeds and direction, humidity, temperatures, or possible precipitation and thunderstorms. Each morning, firefighters read a spot weather forecast for the area specific to where the fire is located. Throughout the day, additional weather is gathered in the field and transmitted via radio to all personnel working on the incident. Crews reply to acknowledge they’ve heard the latest weather reading and are aware of how it may affect the fire’s behavior for the reminder of their day’s shift. 

Photos of a field crew gathering weather data can be found on the Photographs tab of this Inciweb site.

To learn more about wildland fire behavior, visit the National Park Service’s Learning in Depth article at

Lori Iverson
Lone Star Fire Information