• 1 University of Buea

In this paper we present a numerical method for drawing a rainfall map. We use thin plate ajustement spline to fit a smooth surface through meteorological data such as rainfall observations. The determination of the ajustement parameters gives rise to the minimization of a multidimensional nonlinear function whose evaluation is very computational intensive. We propose an heuristic approach for the calculation of the ajustement parameters which is cost effective. The proposed method is tested on a set of rainfall observations gathered by the department of national meteorology in Cameroun.