Fire Weather Maps
The Initial Spread Index is a component of the Canadian Forest Fire Weather Index (FWI) System. It is a numeric rating of the expected rate of fire spread. It is based on wind speed and FFMC. Like the rest of the FWI system components, ISI does not take fuel type into account. Actual spread rates vary between fuel types at the same ISI.
More information about the Canadian Forest Fire Weather Index (FWI) System is available in the Background Information.
Maps updated daily, year-round.