Hydrology-Isohyetal Method

Isohyetal method is a more sophisticated way to calculate mean precipitation over a catchment.

We first join rainfall gauge stations using Delaunay triangulation.

Then, we interpolate the key points on the edges of triangles after knowing the rainfall depth data for all stations.

Finally, we join the key points of the same magnitude using contour line, which is known as isohyet in this case.