What does low relative humidity generally indicate regarding fuel?

Low relative humidity generally indicates that the air is drier, which leads to reduced moisture content in the surrounding environment, including fuels such as grasses, shrubs, and trees. As the relative humidity decreases, the moisture in fine fuels evaporates more quickly. When fine fuels (like grass or small twigs) have lower moisture content, they ignite more easily and burn more readily, leading to an increased potential for fire spread. Dry conditions promote faster and more intense fire behavior, as the flames can move through the dry fuels more effectively.

This relationship between relative humidity and fire behavior is critical for fire management and prevention efforts, as it helps predict how quickly a fire can spread under certain weather conditions. Understanding this concept is essential for firefighters and land management professionals when assessing fire risk and responding to wildland fire incidents.