The user needs to specify the IFD (Intensity- Frequency-Duration) coefficients for 1, 12, and 72-hour intensities for two and 50 year return periods. These coefficients can be obtained from the Australian Rainfall and Runoff (ARR – 1987). The location Skew and Geographic Factors also need to be specified. Instead of Geographic Factors, the user can specify the Latitude and Longitude; in that case XPRafts will estimate the Geographic Factors.

The following link from the Bureau of Meteorology (BOM) will be very useful to get IFD tables/values/charts:

Users can specify the Latitude and Longitude of the area, and obtain the IFD details.