Canadian Wildland Fire Information System

Fire Weather Normals

Buildup Index Daily Severity Rating Drought Code Duff Moisture Code Fine Fuel Moisture Code Fire Danger Fire Weather Index Initial Spread Index April May June July August September Fire Season

 

Fire Danger is a relative index of how easy it is to ignite vegetation, how difficult a fire may be to control, and how much damage a fire may do.

Note: These general fire descriptions apply to most coniferous forests. Choice and interpretation of classes may vary between provinces. For fuel-specific fire behavior, consult the Fire Behavior Prediction maps.

LOW	Fires likely to be self-extinguishing and new ignitions unlikely. Any existing fires limited to smoldering in deep, drier layers.
MODERATE	Creeping or gentle surface fires. Fires easily contained by ground crews with pumps and hand tools.
HIGH	Moderate to vigorous surface fire with intermittent crown involvement. Challenging for ground crews to handle; heavy equipment (bulldozers, tanker trucks, aircraft) often required to contain fire.
VERY HIGH	High-intensity fire with partial to full crown involvement. Head fire conditions beyond the ability of ground crews; air attack with retardant required to effectively attack fire's head.
EXTREME	Fast-spreading, high-intensity crown fire. Very difficult to control. Suppression actions limited to flanks, with only indirect actions possible against the fire's head.
NIL	No calculations were performed for this region.

More information about the Canadian Forest Fire Weather Index (FWI) System and Fire Weather Normals is available in Background Information.

Fire Weather Normals represent the average value of a fire weather code or index over the 30-year period from 1971 to 2000.