Flash propagation and inferred charge structure relative to radar‐observed ice alignment signatures in a small Florida mesoscale convective system

Abstract

Abstract A series of vertical cross sections taken through a small mesoscale convective system observed over Florida by the dual‐polarimetric SMART radar were combined with VHF radiation source locations from a lightning mapping array (LMA) to examine the lightning channel propagation paths relative to the radar‐observed ice alignment signatures associated with regions of negative specific differential phase ( K DP ). Additionally, charge layers inferred from analysis of LMA sources were related to the ice alignment signature. It was found that intracloud flashes initiated near the upper zero‐ K DP boundary surrounding the negative K DP region. The zero‐ K DP boundary also delineated the propagation path of the lightning channel with the negative leaders following the upper boundary and positive leaders following the lower boundary. Very few LMA sources were found in the negative K DP region. We conclude that rapid dual‐polarimetric radar observations can diagnose strong electric fields and may help identify surrounding regions of charge.