ANALYSIS OF THE CHARACTERISTICS OF A HEAVY PRECIPITATION SUPERCELL STORM BASED ON DUAL POLARIZATION RADAR DATA

LI Fang; DIAO Xiuguang; XIA Fan; ZHAO Jingfeng

doi:10.16032/j.issn.1004-4965.2023.072

Abstract：Based on the detection data of an S-band dual polarization Doppler weather radar in Jining,Shandong province,and combined with sounding and surface meteorological observation data,the characteristics of dual polarization parameters and microphysical characteristics of supercells in a heavy rainfall in Shanxian,Shandong province on June 14,2021 are analyzed.The results are shown as follows.The humidity of the whole layer of the environment is relatively high,CAPE is relatively strong,and the height of the 0℃layer is relatively high,which is conducive to the generation of heavy precipitation.Vertical wind shear at moderate intensity is found at the heights of 0～6 km,which is conducive to the generation and maintenance of the supercell storm.The intensity of the supercell storm in Shanxian is 60～65 dBZ at the peak stage,the height of an intensity center is basically below the 0℃level,and the core of mass is low.The height and width of the KDP column are much larger than that of the ZDR column.A strong and wide updraft brings small liquid particles with some degree of concentration to a higher height for extended time.On the left side of the lower storm level,there are always areas of large KDP values,with some of them more than 3 °/km.The concentration of liquid particles is high,and the maximum precipitation rate is maintained at more than 3 mm per minute.On the right side of the lower layer of the storm,there are an inflow gap and a ZDR arc clearly,shown as relatively large liquid particles.There are abundant liquid-and ice-phase particles in the deep thickness above the height of the 0℃layer in the environment.When abundant ice-phase particles drop below the height of the 0℃layer,they melt by large amount.Under the"screening"effect of a strong shear in the lower layer,the junction area between the inflow and the downdraft on the right side of the storm is dominantly with large liquid particles with low concentration and rainfall intensity is low.The lower layer on the left side of the storm has high concentration of liquid particles,resulting in high-intensity precipitation.