How can I create an isohyetal map in ArcGIS 10. I have the precipitation values from a number of weather stations in my area of interest. What tools should I use to create these contour lines?
For contour lines (where you want something visually attractive), the smoothness and the generalisation are important, so I recommend using a spline function for the interpolation. However, this is not necessarily the best method in other applications.
Remark : you need spatial analyst to use these tools in ArcGIS