This dataset contains outputs of numerical modeling for Lake George, New York, hydrodynamics. These numerical simulations were generated to assess the impact of increasing the resolution of weather forecasts on the lake’s thermal state. This research focused on June 2017, when an increase of biological activity was associated to the deepening of the thermocline in the south of the lake. Increasing the resolution of the weather forecast led to a more accurate representation of the water temperature in the lake, including the deepening of the thermocline. The dataset was used in support of “The influence of weather forecast resolution on the circulation of Lake George, NY”.