Abstract:The extreme rainstorm occurred in Zhengzhou on July 20,2021,which caused huge casualties and economic losses.This paper analyzes the rainstorm process by using the data of Luoyang S-band dual linear polarization radar.The results show that the precipitation intensity of this process is large and the duration of heavy precipitation is long.The persistence of strong precipitation echo and upwind area is an important factor causing extreme precipitation in Zhengzhou.The low-quality core structure,the differential reflectivity factor column and the differential propagation phase shift column are all below the height of the melting layer,indicating that the extreme precipitation period in Zhengzhou is dominated by liquid precipitation.The number concentration of flat ellipsoidal heavy raindrops in the heavy precipitation center is high,and the near-surface precipitation efficiency is high.