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Using the data from conventional meteorological observation stations, sounding data, and S-band Doppler and dual-polarization radar data from Qingdao, the weather background and radar echo characteristics of a convective hail event at Qingdao Airport on the afternoon of July 8, 2023 are analyzed. The results show that the hail event occurred under the combined action of a strong westerly wind belt at 500 hPa and a cold vortex trough, with strong local characteristics. The entire atmosphere had strong instability, with obvious characteristics of dryness in the upper layer and wetness in the lower layer. The vertical wind shear intensity in the lower layer was moderate, while the vertical wind shear intensity in the deep layer was strong. The wind vector difference between 0 and 6 km reached 21 m/s, and the temperature difference between high and low altitudes was large. The height at wet bulb temperature 0 ℃ was 4 km. The radar echoes had high-rise strong echoes, bounded weak echo areas, echo hangings, and three-body scattering structures. At the same time, there was a clear mesocyclone structure at an altitude of 4-8 km in the middle layer, with a diameter of about 4 km and a thickness of about 3.2 km in the convergence layer. There was a velocity divergence in the upper layer. These were all typical radar characteristics of hailstorms. The large values of C-VIL and VIL density could well correspond to hail particles, and the C-VIL mutation could also be used as a reference index for forecasting hail and strong winds. The C-VIL jump occurred 30 minutes before the hail at Qingdao Airport, and the sudden drop occurred 7 minutes before the strong wind at Qingdao Airport. During this hail process, the dual-polarisation radar parameters Z_DR and ρ_hv could effectively distinguish hail and strong precipitation, while the K_DP large value area corresponded to heavy rain or melted hail. It was necessary to combine other parameters to further determine the particle morphology. This hail process showed obvious Z_DR and K_DP column structures, with the Z_DR column higher than the K_DP column. The Z_DR column corresponded to strong upward motion, which corresponded to the location of the mesocyclone on the velocity diagram, while the K_DP column corresponded to a more obvious downdraft. The analysis results can provide some reference for short-term and imminent forecasts of hail at Qingdao Airport, and also have some instructive significance for the practical application of dual-polarisation radar products.