Developing and Validating a New Fire-Weather Index Using R2O

Accurate forecasts of weather that affects wildland fire behavior are essential for maintaining the safety of fire personnel as they work to protect life and property while managing wildland fires. Some aspects of fire behavior are straightforward to diagnose because they depend upon environmental factors that vary slowly (e.g., fuel conditions, topography) compared to the weather. As a result, weather conditions that can affect fire behavior are often the most difficult to predict, especially on multi-day timescales. To address the difficulties in forecasting weather conditions that contribute to days when significant fire behavior can occur, we have developed a new fire-weather index, the Hot-Dry-Windy Index (HDW), that gives forecasters, incident meteorologists (IMETs), and other fire practitioners an indicator for use across the United States on the 0- to 7-day timescale.

In this talk, we will describe the O2R and R2O interactions that contributed to the development and implementation of HDW. The HDW development process started from a group of government and university researchers defining a problem that had been identified as a need by IMETs and fire-weather forecasters. From the initial need, we describe how we developed HDW in coordination with the operational community. Then, we describe our beta rollout of HDW to a website for preliminary testing by selected members of the operational community. Finally, we discuss our methodology for using the operational community’s feedback to help us refine the formulation and presentation of HDW so it best serves the needs of everyone who works to manage wildland fires.