The hydrologic frequence analysis makes possible to know the magnitude ofan eventfor a given ocorrency of frequence. It aiso identify wheather the observed data follow some theoretical distribuition of probability. The objective ofthis study was to adjust the observed data ofannual rainfall, as well maximum and minimum monthly rainfall, in several probability leveis, for the agroclimate stations of Pelotas, Morro Redondo, Domingos Petroline and Rio Grande. The series ofannual rainfall data of Pelotas, Morro Redondo, Domingos Petroline and Rio Grande station were adjusted adequately to the normal, log-normal, log-normal and Gumbel distribuitions of probability, respectively. The series of annual maximum were adequate to the Gumbel, log-normal. Gumbel and log-normal distribuitions of probability, respectively. The series of annual minimum for Rio Grande station was not homogeneous by the "Run-Test".
rainfall; distribution; probability
