A Precipitation-Runoff Modeling System (PRMS) model was developed to simulate the surface and near-surface hydrologic system of the Upper Colorado River Basin (UCOL). The model was used to evaluate and compare natural drivers and hydrologic responses of snow processes and evapotranspiration between a recent wet period (1982-1999) and drought period (2000-2022) for four headwater subregions in the Upper Colorado River Basin. This data release child item contains all of the PRMS input and output files for the simulations described in the associated journal article (https://doi.org/10.1016/j.ejrh.2025.102554).