Although ample research suggests that urban environments and their associated land use/land cover modify convective precipitation patterns, little research has explored the role of human-made bodies of water – artificial reservoirs – on thunderstorm climatology. This study provides the first radar-derived climatological analysis of the impact of artificial reservoirs on warm-season convective initiation (CI) and associated thunderstorms. An area centred on three large reservoirs in Southeast Texas is examined to explore how the artificial bodies of water influence the spatiotemporal nature of deep, moist convection. A thunderstorm day and CI climatology for the study domain is constructed utilizing composite radar reflectivity data from 1997 to 2013. The results illustrate enhanced (reduced) convective activity on the edges of (atop) the reservoirs. The presence of the reservoirs also induced increased variability in thunderstorm occurrence compared to areas with no reservoirs. In addition, spatial analytical testing yields statistically significant higher densities of CI events on the southern shores of the reservoirs. Evidence that relatively small bodies of water can influence regional convective patterns and modify the risk of thunderstorm hazards is presented.