Spatiotemporal relationship between lightning activity and Z_DR/K_DP columns in the South China squall lines

This study analyzes the relationship of spatiotemporal configuration between lightning activities and Z_DR and K_DP columns during two squall lines over Guangzhou on 4 and 8 May 2017. The observations are from a S-band dual-polarization radar and the Low-Frequency Electric Field Detection Array. The results show that: (1) During the early stage of lightning activities (the intracloud (IC) lightning frequency is less than 50/(6 min), and the cloud-to-ground (CG) lightning frequency is less than 10/(6 min)), IC lightning and CG lightning mainly occurred within the plane spatial coverage of Z_DR and K_DP columns, and IC lightning tended to occur within the area of K_DP columns (the maximum percentage can exceed 40%). As lightning activities became more active, IC lightning and CG lightning activities mainly occurred outside the planar coverage of the Z_DR and K_DP columns. (2) Changes in Z_DR and K_DP column volume led the trend of the IC lightning and CG lightning activity by about 30 min, and the correlation coefficient approached or exceeded 0.9. In addition, the peak of Z_DR column volume was a good predictor of the occurrence of IC lightning and CG lightning peak. The results of this study have important scientific significance for understanding the relationship between lightning activities and the dynamic structure of the complex mesoscale weather systems. It also provides new perspectives for early warning and forecasting of lightning activities via dual-polarization weather radar data.