In this study an attempt has been made to evaluate rainfall distribution patterns i.e. weekly, seasonal and annual rainfall, based on 31 years (1965–1995) data of Patna, Bihar. The analysis showed that amongst various weeks of monsoon season, the 30th week received highest rainfall amount equal to 461.9 mm. However, average rainfall as 92.6 mm was found to be highest for 29th week. Amongst seasonal rainfall distribution, the monsoon season received highest average rainfall i.e. 952.6 mm. The annual average rainfall was computed as 1171.1 mm. The work was further extended to evaluate rainfall distribution at different recurrence intervals i.e. 2, 5, 10, and 25 years by using Weibull's Method. Mathematical relationships between rainfall and recurrence interval, were also developed.
