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Using the Sband dualpolarization Doppler radar in Bengbu, the tornado weather on 22 July 2020 in Suzhou, Anhui Province is analyzed in detail. The results show that under the situation of a rainstorm in the Meiyu period，the lower lifting condensation level and strong vertical wind shear in the middle and low levels provided a favorable environment for the tornado. The tornado occurred in a supercell storm at the southern end of the Meiyu front. There was a hook echo at the right rear of the bottom layer of the supercell. The rapid changes of storm parameters, mesocyclone and TVS (Tornado Vortex Signature) parameters are good indications for early warning and judgement for the occurrence of the tornado. Before the occurrence of the tornado, the maximum reflectivity, vertical accumulated liquid water and top height of the individual storm all increased, while the bottom height decreased significantly. The tornado occurred when the maximum reflectivity factor height dropped rapidly to the bottom. The radar detected the mesocyclone and TVS, 24 and 42 minutes, respectively, before the tornado occurred. Meanwhile the top height of the mesocyclone increased significantly and the maximum hear height dropped sharply. The tornado occurred when the bottom height dropped below 1 km. The top height dropped suddenly and the maximum hear height dropped to the bottom of the mesocyclone. Before the occurrence of tornado, the TVS top height and the maximum shear increased, and the maximum shear height decreased. When the tornado occurred, the top height decreased, and the maximum shear height also decreased to the bottom of TVS. The zerolag correlation coefficient and the tornadic debris signature (TDS) in the low differential reflectance area were observed at the end of the bottom hook echo.