Abstract:Based on the hourly and daily precipitation data of national meteorological stations in Southwest China, the climatic characteristics of short time severe precipitation are analyzed. In addition, the variation trend of short time severe precipitation and severe rainstorms surpassing 90 percentile are analyzed as well. The results show that the short time severe precipitation over Southwest China mainly occurs from April to October. The three regions where short time severe precipitations are seen most frequently are located in the southeast of Guizhou Province, the southwest of Sichuan Basin, and the southeast of Yunnan Province, respectively, with average frequency is 5-6 times annually. Generally, the intensity is 20-30 mm·h-1, with the highest proportion of more than 30 mm·h-1 in Guizhou. The highest intensity occurs in the western edge of Sichuan Basin where the intensity is over 80 mm·h-1. The extreme hourly precipitation is 123.1 mm·h-1. Moreover, the nocturnal feature of the short time severe precipitations is evident and the wee hours around 02:00 am is the summit period. The long term trend of severe precipitation and rainstorm in Southwest China for the period of 1981-2010 indicates that the frequency of the heavy short time severe precipitations is increasing and the intensity becomes enhanced. For severe rainstorms, the trend is not evidently changed.