The Objective of this study is to understand the change in precipitation extreme due to climate change for stormwater management in Yato watershed, Tokyo. The study site was selected such that solutions can address the dual challenges of climate change and urbanization. In this study, we have employed GCM precipitation output from GFDL-CM3 for assessing the impact of climate change on precipitation pattern over Yato Watershed. Observation precipitation data of 1976-2005 periods were compared with the corresponding GFDL-CM3 precipitation data for identifying the biases. Consequently, Quantile-based bias correction was employed to correct the GCM precipitation data of 2071-2100 periods as future climate for the impact assessment. Further, simple scaling technique was applied for deriving the short duration rainfall intensities from available rainfall data. The scaling behavior of observation rainfall intensities was examined and it was revealed that the statistical properties of observation rainfall follow the assumption of simple scaling. A total of seven different durations for return periods of 2, 5, 10, 25, 50 and 100 years were analyzed for preparing the IDF curves. Comparison of IDF curves for present and future climate indicated a significant increase in maximum rainfall intensities which has major implications on planning and design of urban stormwater drainage systems.