Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Ralph M. Nelson
    Date: 2002
    Source: International Journal of Wildland Fire. 11: 153-161.
    Publication Series: Scientific Journal (JRNL)
    Station: Rocky Mountain Research Station
    PDF: Download Publication  (160.0 KB)


    In previous descriptions of wind-slope interaction and the spread rate of wildland fires it is assumed that the separate effects of wind and slope are independent and additive and that corrections for these effects may be applied to spread rates computed from existing rate of spread models. A different approach is explored in the present paper in which the upslope component of the fire’s buoyant velocity is used with the speed and direction of the ambient wind to produce effective values of wind speed and direction that determine the rate of spread vector. Thus the effective wind speed can replace the ambient wind speed in any suitable fire spread model and provide a description of the combined effects on the fire behavior. The difference between current and threshold values of the effective wind speed also can be used to determine whether fire will spread in a given fuel type. The model is tested with data from experiments reported by Weise (1993) in which fire spread was in response to variation in both wind speed and slope angle. The Weise spread rate data were satisfactorily correlated using dimensional methods and the observed spread rate was reasonably well predicted with an existing rate of spread model. Directional aspects of the model were not tested because the Weise (1993) study did not include winds with a cross-slope component.

    Publication Notes

    • You may send email to to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • 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.


    Nelson, Ralph M., Jr. 2002. An effective wind speed for models of fire spread. International Journal of Wildland Fire. 11: 153-161.


    Google Scholar


    wind/slope interaction, threshold wind speed, fire behavior, spread direction

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page