The Hot-Dry-Windy Index: R2O, the Cloud, and Ongoing Development

Since its launch in 2018, the Hot-Dry-Windy Index (HDWI) has become an integral component of fire weather forecasting operations in multiple regions of the United States. Forecasters in National Weather Service forecast offices and Incident Meteorologists on location during wildfires use the product to help determine and communicate how weather conditions can make a wildland fire difficult to manage. Additionally, the HDWI has been used in a number of research projects to investigate weather-related fire activity across a range of spatial and temporal scales, and it has featured in investigations and the associated reports of a number of historical fires.

This presentation will review the process by which HDWI was transferred from research to operations (R2O). Recent and ongoing efforts to update and modernize how HDWI is calculated and delivered will be described. Specifically, the process by which the HDWI system was moved to a new cloud-based server managed by the US Forest Service using Amazon Web Services technology will be detailed, and the implications of this move for users will be discussed. Finally, recent, ongoing, and future efforts to refine and update the HDWI and, more broadly, other hot-dry-windy-based applications will be presented.