A hyetograph is a graphical representation of the distribution of rainfall intensity over time.
For instance, in the 24-hour rainfall distributions as developed by the Soil Conservation Service (now the NRCS or National Resources Conservation Service), rainfall intensity progressively increases until it reaches a maximum and then gradually decreases.
In other words, a real storm may not behave in this same fashion.
The maximum intensity may not be reached as uniformly as shown in the SCS hyetographs.
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