The synoptic setting of thunderstorms in western Europe

This paper discusses the synoptic factors contributing to the formation of thunderstorms in western Europe and in particular gives reasons for the existence of the preferred areas for thunderstorms. These areas are all found in the vicinity of the Alps. The synoptic features playing a role in promoting thunderstorm formation in particular areas in western Europe are identified. The principle synoptic features or processes promoting the formation of intense thunderstorms are a high level of potential instability, convergence lines associated with frontogenesis and cyclogenesis and upper level potential vorticity advection. Additional features playing a role in thunderstorm formation are land and seabreeze circulations and (thermally) forced upward motion at slopes.