Flash cells in thunderstorms

Abstract

When convection develops into a thundercloud stage of at least moderate intensity, its cellular appearance may be monitored not only with weather radars but also with lightning location systems. For intense thunderstorms, the ground-flash rate alone is sufficient for making apparent the underlying convection-cell structure. if flash cells can be properly identified, they show longitudinal development complementary to the usual view of advancing transverse front. A method is described to analyse the flash-cell structure of thunderstorms and is illustrated with an example from Finland. With proper choice of parameters, the largest, most interesting flash cells generally have realistic sizes, lifetimes and motion. © Springer Science+Business Media B.V. 2009.