This data release contains daily mean squared logarithmic error (MSLE), as well as several decompositions of the MSLE, for three streamflow models: nearest-neighbor drainage area ratio (NNDAR), a simple statistical model that re-scales streamflow data from the nearest streamgage; the National Hydrologic Model Infrastructure application of the Precipitation-Runoff Modeling System (NHM-PRMS); and version 2.0 of the National Water Model (NWM). Error was determined by evaluating each model daily against streamflow observations from 1,021 ‘reference’ (minimally anthropogenically impacted [Falcone, 2011]) watersheds across the conterminous United States with at least 10 years of observations. References: Falcone, J.A., 2011, GAGES-II: geospatial attributes of gages for evaluating streamflow: U.S. Geological Survey data release, https://doi.org/10.3133/70046617.