An analysis of the rainfall distribution with altitude in the western region of El Salvador is made, utilizing several stations along a topographic profile. It is found that rainfall increases with altitude, reaching a maximum value in the top half of the mountain slopes. The rainfall maximum in the southern slope of Volcan Santa Ana is larger than the corresponding maximum on the northern slope. In addition, it is found that a quadratic equation provides a good adjustment to such a rainfall distribution, except in October where a cubic equation provides a better adjustment.
