The Water Erosion Prediction Project (WEPP) model, originally developed for hillslope and small watershed applications, simulates complex interactive processes influencing erosion. Recent incorporations to the model have improved the subsurface hydrology components for forest applications. Incorporation of channel routing has made the WEPP model well suited for large watersheds. However, the model is still limited in modeling forested watersheds where groundwater baseflow is substantial, and where snow accumulation and melt dominate winter hydrology. A linear-reservoir model was used to estimate baseflow and a double-threshold temperature approach was used to partition precipitation into snow and rain. A mountainous subwatershed of the Upper Cedar River watershed was chosen for WEPP application and assessment. Simulations were conducted for 1996–2011 to assess the model. The WEPP model reproduced the majority of observed streamflow peaks and the general trend of the hydrograph demonstrating its applicability to a large watershed where groundwater baseflow was significant.