Skip to Main Content
The hot-dry-windy index: A new fire weather indexAuthor(s): Alan Srock; Joseph Charney; Brian Potter; Scott Goodrick
Publication Series: Scientific Journal (JRNL)
Station: Southern Research Station
View PDF (1.0 MB)
DescriptionFire weather indices are commonly used by fire weather forecasters to predict when weather conditions will make a wildland fire difficult to manage. Complex interactions at multiple scales between fire, fuels, topography, and weather make these predictions extremely difficult. We define a new fire weather index called the Hot-Dry-Windy Index (HDW). HDW uses the basic science of how the atmosphere can affect a fire to define the meteorological variables that can be predicted at synoptic-and meso-alpha-scales that govern the potential for the atmosphere to affect a fire. The new index is formulated to account for meteorological conditions both at the Earth’s surface and in a 500-m layer just above the surface. HDW is defined and then compared with the Haines Index (HI) for four historical fires. The Climate Forecast System Reanalysis (CFSR) is used to provide the meteorological data for calculating the indices. Our results indicate that HDW can identify days on which synoptic-and meso-alpha-scale weather processes can contribute to especially dangerous fire behavior. HDW is shown to perform better than the HI for each of the four historical fires. Additionally, since HDW is based on the meteorological variables that govern the potential for the atmosphere to affect a fire, it is possible to speculate on why HDW would be more or less effective based on the conditions that prevail in a given fire case. The HI, in contrast, does not have a physical basis, which makes speculation on why it works or does not work difficult because the mechanisms are not clear.
- Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat.
- During the capture process some typographical errors may occur.
- Please contact Sharon Hobrla, firstname.lastname@example.org if you notice any errors which make this publication unusable.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationSrock, Alan; Charney, Joseph; Potter, Brian; Goodrick, Scott. 2018. The hot-dry-windy index: A new fire weather index. Atmosphere. 9(7): 279-289. 11 p. https://doi.org/10.3390/atmos9070279.
Keywordsfire weather, index, Haines Index
- Combining turbulent kinetic energy and Haines Index predictions for fire-weather assessments
- Interannual variations in fire weather, fire extent, and synoptic-scale circulation patterns in northern California and Oregon
- Climatic variability of a fire-weather index based on turbulent kinetic energy and the Haines Index
XML: View XML