Estimates of streamflow are critical to inform natural resource managers about water availability for both human and ecological needs. Monitoring streamflow using a streamgage provides information about the amount and timing of surface water resources. However, hydrologic models can be used to provide estimates of streamflow in the absence of streamflow information and assess the potential effects of changes in climate and land cover on hydrologic response. The USGS has developed a National Hydrologic Model to support coordinated, comprehensive and consistent hydrologic model development, and facilitate the application of hydrologic simulations within the conterminous United States. Jacob LaFontaine's research developed hydrologic simulations for historical and potential future climate and land cover to characterize watersheds across the southeastern United States. These hydrologic simulations provide estimates of water availability and streamflow characteristics and provide a methodology for further National Hydrologic Model development.