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IDF Curve Tool
Open nc file by using the list of coordinates

What is rainfall intensity duration frequency (IDF)?

An IDF (intensity duration frequency) curve is a mathematical function that relates the rainfall intensity with its duration and frequency of occurrence. The rainfall IDF (intensity duration frequency) curves play an important role in water resources management engineering. The rainfall IDF (intensity duration frequency) curves are graphical representations of the probability that a given average rainfall intensity will occur within a given period of time. The IDF curves can take different mathematical expressions, theoretical or empirically fitted to observed rainfall data. The first IDF curve was established as early as 1932, whilst since then many sets of IDF relationships have been constructed for several parts of the world.

What is IDF Curve Tool?

The IDF curve tool can draw IDF charts by using several methods. You have two options to input data. In the first tab, you can input your raw data in 5-min to daily scale then the IDF tool will calculate maximums in the second tab. But also you can input the maximums in the second tab instead of raw data. In the third tab, you can draw IDF graphs for any return periods. A return period is an average time or an estimated average time between events(intensity of rainfall occurrence). You can save the IDF data in an excel file and draw the IDF graphs in Excel.

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IDF Curve Tool