According to this website, the fire danger indicators currently presented in this report are components of the Canadian Forest Fire Weather Index (FWI) System. The Global EWS provides 1-7 day forecasted FWI System data based on the National Centers for Environmental Prediction (NCEP) Global Forecast System. The FWI System components are currently calibrated to commonly used threshold values that identify low to extreme conditions. As such, the Global EWS provides a means of comparing relative fire danger conditions between countries, continents and biomes; and the 1-7 day forecast identifies the expected future fire danger trend.