Effect of climate change on hydrologic flow regimes, particularly extreme events, necessitates modeling of future flows in order to best inform water resources management. This study simulated future flows in the Cache Creek watershed in California over the 21st century using a hydro-climate model (Watershed Environmental Hydrology Hydro-Climate Model; WEHY-HCM) forced by future climate projections. The future climate projections, based on four emission scenarios simulated by two global climate models (GCMs), the fifth-generation atmospheric global climate model and third-generation community climate model (ECHAM5 and CCSM3), under several initial conditions, were dynamically-downscaled using the fifth-generation mesoscale atmospheric model (MM5), a regional climate model. The downscaled future precipitation data were bias-corrected before being input into the WEHY model to simulate the detailed flow at hourly intervals along the main Cache Creek branch and its tributaries during 2010–2099. The re...