The following are the published equations used for the complete calculation cycle for McArthur Mk 5 Forest Fire Danger Index. All equations are sourced to original references. All inputs are metric. All references to the functions Log and Exp are in base e .
All inputs are real numbers.
Do not round off to integers, except for display purposes. 4 DSLR Days since last rain. Note also DSLR may be calculated off the day of heaviest rainfall, if subsequent rainy days had only light rainfall. Another feature of the onset of a new rain spell is that the canopy is dry and can intercept its full assumed 5mm of rain. Note too that the BKDI model makes no use of wind, even though strong winds may dry out the canopy.