This study investigates changes and uncertainties to cool-season (November-March) storm tides along the U.S. northeast coast in the 21st century under the high RCP8.5 emission scenario compared to late 20th century. A high-fidelity (50-m coastal resolution) hydrodynamic storm tide model is forced with three dynamically-downscaled regional climate models (RCMs) over three decadal periods (historical, mid-21st century and late-21st century) to project future changes in peak storm tide elevations at coastal counties in the region. While there is no absolute consensus on future changes to storm tides, for any one future decade two out of the three RCMs project an increase at counties along the Hudson River, Delaware River and northern Chesapeake Bay due to more intense cyclones that track inland of these locations leading to favorable surge generating conditions. The same RCMs also project a decrease at counties facing the open ocean in the mid-Atlantic Bight as cyclone densities just offshore of the coastline decrease, particularly by late-century. The larger tidal range in northern areas leads to significant uncertainty due to the arbitrary relationship between the local tidal stage and when a surge event occurs, which affects both the magnitude and sign of the projected changes. This tide-surge timing is less important in the Chesapeake Bay and unimportant in Albemarle Sound and Pamlico Sound. Similar to other recent studies, we highlight that sea level rise is likely to be more critical than storm climatology for future changes to the cool-season coastal flooding potential.