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By means of the daytoday precipitation data from 1951 to 2004 in Jilin Province, the characteristics of major rainfall events are analyzed and the single and synthetical evaluating indexes that can reflect the severity of heavy rainfall are built. The evaluation grades of heavy rainfall events are devised. The normality test of the synthetical evaluation index is conducted by using the kurtosis and skewness coefficients of the synthetical evaluating indexes. The synthetical evaluation indexes obey the normal distribution, so the evaluation indexes for the recurrence period of abnormal climate are given. By using the indexes of evaluation grades and the evaluation indexes for the recurrence period of abnormal climate, the heavy rainfall events from 2005 to 2006 are evaluated. The results show that the method is feasible and can satisfy the requirements of operational application.