This dataset contains the input (temperature and precipitation from climate models) and output from the Soil and Water Assessment Tool (SWAT) model runs using the Hydrologic and Water Quality System (HAWQS) platform (https://hawqs.tamu.edu/). The HAWQS platform is an online tool developed by Texas A&M and US EPA to allow scientists and decision-makers to run large scale watershed simulation models using the Soil & Water Assessment Tool (SWAT) model without the need to download/install software, gather input data, perform initialization steps, or use up local computer resources. We ran the model at the Hydrologic Unit Code-8 scale over Region 3 of the United States Fish and Wildlife Service (Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin). The climate inputs were historic temperature and precipitation from the Parameter-elevation Relationships on Independent Slopes Model (PRISM), and future projections using downscaled Localized Constructed Analogs (LOCA). We used five LOCA downscaled climate models (CanESM2, CCSM4, GISS-E2-R, HadGEM2-ES, and MIROC5) and two Representative Concentration Pathways (RCP 4.5 & RCP 8.5). The output from the SWAT model consisted of two files, the subbasin file containing metrics related to the watershed, and the reach file containing metrics from the stream/river. All inputs and outputs are on daily timesteps. We summarized the hydrologic outputs at monthly or annual time scales before analysis because comparisons with historic gage data showed the monthly and annual estimates performed better than the daily estimates.