A 2016 update was made to the GSFLOW model documented in SIR 2013-5159, which is available online ( https://pubs.usgs.gov/sir/2013/5159/ ). The original GSFLOW model was created to simulate climate changes effects on streamflow, lake budgets, and stream temperature in the Trout Lake Watershed, Wisconsin. The computer code GSFLOW (Groundwater/Surface-water FLOW) was used to simulate the coupled hydrologic system; a surface-water model represented hydrologic processes in the atmosphere, at land surface, and within the soil-zone, and a groundwater-flow model represented the unsaturated zone, saturated zone, stream, and lake budgets. The coupled GSFLOW model was calibrated by using heads, streamflows, lake levels, actual evapotranspiration rates, solar radiation, and snowpack measurements collected during water years 1998–2007; calibration was performed by using advanced features present in the PEST parameter estimation software suite. The updated model for this data release extended the simulation period to 1975-2015 (first 13 years discarded as spin-up) as compared to 1988-2007 (first 12 years discarded as spinup) for the original GSFLOW model of SIR 2013-5159.