Probable maximum point rainfall estimation for the southern half of the Indian peninsula

Preparation of a generalized chart of probable maximum precipitation (PMP) for the southern half of the Indian peninsula lying between lat. 8°N to 16°N has been attempted in this study. Maximum 1-day rainfall data of 70 to 80 years from 1891 for about 600 stations in the peninsular states of Tamil Nadu, Kerala, South Karnataka and southern portions of Andhra Pradesh were used. In order to get appropriate values of PMP, envelope frequency factor (K _m) curve based on the actual rainfall data of the region was prepared. This study has shown that one-day PMP estimates over this region range from about 25 cm to about 85 cm. The heavy rainfall received over the coastal areas of Tamil Nadu in association with the cyclonic disturbance of November 1976 was examined and it was found that this rainfall was nowhere near the PMP estimates for this area.