Regional climate simulations over the Great Lakes region were evaluated using three different global data sets. The simulations showed better accuracy in winter than in summer and were more accurate at higher altitudes. The simulations captured the impact of the Great Lakes on the region's climate, especially in winter precipitation. However, there were biases in the simulations, such as a cold bias over the lakes and an overestimation of non-convective precipitation. The simulations driven by different global data sets had varying levels of success in capturing temperature and precipitation patterns, with some overestimating cold-season precipitation and underestimating summer precipitation. Overall, the simulations provided valuable insights into the regional climate dynamics, highlighting the importance of accurate boundary conditions and sea-surface temperatures in climate modeling.