This paper had as its objective the study of the rainfall behavior in the rainy season in the area of Diamantina, MG, Brazil. Monthly rainfall data of historical series from 1977 to 2006 were used. The probability was checked of several rainfall classes through the accumulated frequency function using the Weilbull's distribution methodology with adherence verification by Kolmogorov-Smirnov test with significance level of 5%, classes defined by predetermined percentage. The results show that the rainy season, between October and March, represents 88% of the annual rainfall. The months of January and December presented the largest probabilities of rainfall with 220.1 mm and 167.8 mm, respectively, at a level of 25% of occurrence probability. The Weilbull distribution model presented a good adjustment of the climatic series for probabilities studies, showing the parameters within the statistical limits established before.
agriclimatology; Weilbull distribution; rain probability