Identification of convection cells and the effect of hail suppression during a hail event

Based on conventional meteorological data during a hail event in the northwestern Shandong province from June 12 to 13, 2018, we analyzed the synoptic situation and physical quantity conditions for the hail formation.The results indicated that the radar echo index has an obviously decreasing trend before and after the operation of artificial hail suppression.The values of liquid water path (LWP) and echo top height index decrease by 49.9% and 37.4%, respectively.Hail probability drops from 99.3% to 28.7% after the hail suppression operation.The echo intensity, echo top height, and LWP values decrease by 10 dBz, 7 km, and 48 kg·m^-2 at most, respectively.In a comparison of the development and evolution of two similar convection cells, the hail suppression operation makes echo intensity, echo top height, and LWP value of one convection cell decrease by 7 dBz, 3 km, and 11 kg·m^-2, respectively, and then results in a large fluctuation in hail probability.The echo intensity and top height become higher and hail probability drops more quickly after the hail suppression.While the other convection cell without the effect of hail suppression has smaller fluctuation in radar echo indexes during the numbering period of convective cells, which further proves the positive effect of the artificial hail suppression.