Fire Danger Rating System
A fire danger rating system converts daily weather, fuel, and topography information into operational indices that summarize how easily wildfires will ignite, spread, and burn intensely. Two systems dominate worldwide practice: the U.S. National Fire-Danger Rating System (NFDRS), documented by Deeming, Burgan, and Cohen, and the Canadian Forest Fire Weather Index (FWI) System, whose structure Van Wagner formalized in 1987. Both begin by tracking the moisture content of fuels of different sizes — fine fuels respond to weather within hours, while heavy logs and deep duff respond over weeks — and then feed these moisture estimates, together with wind and fuel characteristics, through a chain of subindices that estimate rate of spread, fuel consumption, and fire intensity. The end product is a small set of numbers and danger classes (from Low to Extreme) that agencies use to set preparedness levels, issue public warnings, position resources, and impose restrictions.
Source record
Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.
- Deeming, J. E., Burgan, R. E., & Cohen, J. D. (1977). The National Fire-Danger Rating System — 1978. General Technical Report INT-39, USDA Forest Service, Intermountain Forest and Range Experiment Station, Ogden, UT, 63 p. · URL
- Van Wagner, C. E. (1987). Development and Structure of the Canadian Forest Fire Weather Index System. Forestry Technical Report 35, Canadian Forestry Service, Ottawa, 37 p. · URL
Curated claims
Claims persisted in the evidence ledger, each with its own assessment.
This view does not invent a claim assessment when the ledger has none.
Related methods
Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.