Lightning Characteristics and Electric Charge Structure of a Hail-Producing Thunderstorm on the Eastern Qinghai–Tibetan Plateau

An isolated hail-producing thunderstorm that occurred on 20 August 2012, from the Composite Observing Experiment for Lightning project carried out in the Da Tong Region of Qinghai Province, China, was studied. In most stages, the charge structure in the storm showed a positive tripole structure, which resulted in a low positive ground lightning rate for the whole event. In the thunderstorm process, 202 lightning flashes were detected. The peak lightning rate of lightning was 28 times/5 min. The average number of return strokes of negative ground flash was 2.4, and only one return stroke of positive ground lightning occurred. The duration of the in-cloud process prior to the first return stroke was relatively long. Dynamic transport had a considerable influence on the charge structure of the cloud. Before and after hail landing, the ground electric field of several stations showed a consistent trend of reversal.