The Suizhou Sband dualpolarization radar data and conventional observations are used to analyze a supercell in the northern Hubei on 4 May 2020. The results show that: (1) The favourable weather conditions provided the vertical stratification of dry and cold in the upper part and warm and wet in the lower part, moderateintensity vertical wind shear in 0 to 6 km and the surface convergence line. They provided the environmental conditions and trigger conditions for the strong storms. (2) During the supercell development, the front “V” inflow gap, mesocyclone, weak echo dome, drape echo and hook echo were observed. Moreover, the storm top, the centre of storm mass, the height of maximum horizontal reflectivity factor and the VIL showed the trend of first rising and then falling. (3) During the development and maturity of the supercell, a shallow region of high differential reflectivity was found along the large gradient region on the west of forwardflank downdraft below 0 ℃ which was termed as Zdr arc. (4) During the beginning, development and maturity stages of the supercell, a midlevel circular ring of enhanced Zdr and depressed R was found above the 0 ℃ layer, formed by the melting of ice particles due to the positive temperature disturbance strong updraft. (5) In the vertical direction, the Zdr and Kdp columns were observed in the supercell’s beginning, development, and maturity stages. The position of the Zdr column was consistent with a weak echo dome, and its characteristics in different periods reflected the change of updraft intensity; the change of the Kdp column demonstrated the change of liquid droplet region in the supercell.