Abstract:
This study uses lightning location, precipitation and radar data to analyze the characteristics of cloud-to-ground (CG) lightning activity and its relationship with precipitation in Meizhou, Guangdong Province in April 2024. The results show that the correlation between positive CG lightning and precipitation is stronger than that between total CG lightning and precipitation. Lightning-related precipitation fluctuates synchronously with the lightning frequency and decreases at night as the lightning weakens, and lightning-related precipitation contributes less to night-time precipitation. Through the analysis of 15 thunderstorm processes, it is found that thunderstorms with a higher positive flash ratio tend to have less lightning-related precipitation. Conversely, thunderstorms with a lower positive flash ratio bring more lightning-related precipitation and contribute more to the total precipitation of the entire process. However, the linear relationship between lightning and precipitation varies in different processes. There is no obvious correspondence between the extreme values of CG lightning and precipitation, and they rarely reach their peaks simultaneously. Further analysis of a thunderstorm case elucidates that negative CG lightning is more concentrated than positive CG lightning, mainly distributed in the area with a high echo-top height gradient. The distribution area of positive CG lightning is discontinuous, not only in the area with high radar reflectivity factor but also in the stratiform cloud area behind the strong precipitation cloud system. The area with the most active lightning corresponds well to the strong precipitation area, and the stronger the precipitation, the more concentrated the lightning activity.