Relating cloud microphysical properties and lightning: Model analysis of an Extreme Hailstorm

The University of Washington, 1.5-dim thunderstorm model (UWTM) is used to model microphysical cloud properties and related electrical activities of convective cells associated with the 3-5 August 2002 storm over the Po Valley (Northern Italy). Thee MM5 mesoscale model, which has been used to analyze the development of this severe storm, is used to initialize the UWTM at various locals to obtain a large collection of lightning, precipitation and microphysical profiles for this event. The performance of the models have been evaluated by comparing the results from lightning flash rate (from ground based lightning sensors) and cloud reflectivity (from a C band ground based radar). This study is important, due to the relationships between microphysical parameters (e.g., ice and liquid water content, hydrometeor size and distributions obtained from the UWTM output) to better represent the vertical microphysical structure of lightning producing clouds within mesoscale models or nowcasting when lightning observations are available.