Tropical storm Danny intensified dramatically as it traversed the Piedmont of the Carolinas on 23-24 July 1997. Analysis of in-situ surface data reveals that over a 12-h period the storm's central pressure decreased by more than 5 mb and peak wind speeds doubled. Simultaneously, a strong reflectivity core formed near the circulation center as seen on nearby WSR-88D radars. The core convection appeared to form a rudimentary eye-wall structure while the storm center was at least 190 km from the coast. The role of latent heat release, weak vertical wind shear, adiabatic subsident heating, and upper-level baroclinic support are explored as possible explanations for the storm intensification