The model simulation that drives the early warning system and disease alerts start at the beginning of the wheat season. For each grid call found on the map, the model simulates the number of spores that are present in the air. These, in turn, express the amount of inoculum that builds up during the wheat vegetative growth period. The model assumes that inoculum is present in the environment contained within the grid cells and that it originates from host plant tissues. These include wheat, but could also include secondary hosts such as weeds. Based on the estimated number of spores in the air, each grid cell is empirically categorized into one of three bins – (1) no risk, (b) moderate risk, and (3) high risk – signified by different colors to indicate the risk of an outbreak. The squares in green represent no risk while yellow and red squares indicate, respectively, moderate and high risk. A risk map is available for each of the five days forecasted.

This model generates wheat blast warnings for Bangladesh only from January 9 through April 4 of each year, as these dates correspond to the periods of the crop calendar during which wheat is most at risk of disease infection