The program Forecast of Runoff Model (MPE) was developed with the intention of foretelling the runoffs of a river basin by means of a distributed parameters model. The method used for the production of runoff is based on the method of the Soil Conservation Service (SCS) with a modification that allows considering the drying of the ground after a rain. The transference of the runoff is made using the modified Clark method. The program works with the information of the installed pluviograph network in the river basin and with the hydrologic parameters of the river basin in mesh form obtained with the aid of a GIS (Geographic Information System). The model is able to obtain: the average precipitation in the river basin, its hyetograph, rain in excess, losses and the hydrograph at the outflow of the river basin.