Canadian Forest Service Publications
Development and structure of the Canadian Forest Fire Weather Index System. 1987. Van Wagner, C.E. Canadian Forestry Service, Headquarters, Ottawa. Forestry Technical Report 35. 35 p.
Issued by: National Capital Region
Catalog ID: 19927
The Canadian Forest Fire Weather Index (FWI) System was first issued in 1970 after several years' work by a number of fire researchers in the Canadian Forestry Service. The best features of the former fire danger index were incorporated in the FWI, and a link was preserved between old and new. The FWI is based on the moisture content of three classes of forest fuel plus the effect of wind on fire behavior. The system consists of six components: three primary subindexes representing fuel moisture, two intermediate subindexes representing rate of spread and fuel consumption, and a final index representing fire intensity as energy output rate per unit length of fire front. The FWI System refers primarily to a standard pine fuel type but is useful as a general measure of forest fire danger in Canada. Its components are determined every day from noon weather readings: temperature, relative humidity, wind speed, and rain (if any). The development of the Fire Weather Index, the concepts behind it, and its mathematical structure are described in this paper. Revised versions of the Fire Weather Index System were issued in 1976 and 1984.
Also available under the title:
Élaboration et structure de la méthode canadienne de l’Indice Forêt-Météo (French)