|These maps are produced by interpolating weather that is valid for noon of the day shown. You can view temperatures and indices directly by weather station or view a station location map.
Canadian Forest Fire Weather Index System (FWI)
The six standard components of the FWI System provide numerical ratings of relative wildland fire potential. The first three components are fuel moisture codes that follow daily changes in the moisture contents of three classes of forest fuel with different drying rates. For each, there are two phases - one for wetting by rain and one for drying - arranged so that the higher values represent lower moisture contents and hence greater flammability. The final three components are fire behavior indexes, representing rate of spread, amount of available fuel, and fire intensity; their values increase as fire weather severity worsens.
The system is dependent on weather only and does not consider differences in risk, fuel, or topography. It provides a uniform method of rating fire danger across Canada. The six components are described below.
Fine Fuel Moisture Code (FFMC) Canadian FFMC Map
A numerical rating of the moisture content of litter and other cured fine fuels. This code is an indicator of the relative ease of ignition and flammability of fine fuel.
Duff Moisture Code (DMC) Canadian DMC Map
A numerical rating of the average moisture content of loosely compacted organic layers of moderate depth. This code gives an indication of fuel consumption in moderate duff layers and medium-size woody material.
Drought Code (DC) Canadian DC Map
A numerical rating of the average moisture content of deep, compact, organic layers. This code is a useful indicator of seasonal drought effects on forest fuels, and amount of smouldering in deep duff layers and large logs.
Initial Spread Index (ISI) Canadian ISI Map
A numerical rating of the expected rate of fire spread. It combines the effects of wind and FFMC on rate of spread without the influence of variable quantities of fuel.
Buildup Index (BUI) Canadian BUI Map
A numerical rating of the total amount of fuel available for combustion that combines DMC and DC.
Fire Weather Index (FWI) Canadian FWI Map
A numerical rating of fire intensity that combines ISI and BUI. It is suitable as a general index of fire danger throughout the forested areas of Canada.
Manitoba maps vary slightly in color and contours from Canadian Maps due to different legend groupings and colours. Both map sets are produced with raw data from Manitoba Fire Program weather stations, and Environment Canada weather stations.
For additional information regarding Forest Fire Research and Technology in Canada visit The Canadian Wildland Fire Information System home page