This work, developed by engineer Abias Porfírio Cinco Reis, is a relevant contribution to teaching and professional and scientific training in the areas of water resources, hydrology, agronomy and forestry sciences, both at undergraduate and postgraduate level, as well as to the community in general in understanding the processes of the hydrological cycle through which water passes in nature, as well as its applications in the terrestrial phase of the hydrological cycle, with a greater focus on the precipitation process for agricultural planning. The work is the result of research carried out in one of Angola's municipalities (Cuito-Bié), a potentially agricultural region with high rainfall at certain times of the year, but without much meteorological information to analyze the behavior of this variable, which is quite fundamental in hydrological studies.