Based on conventional observation data, Doppler weather radar data and wind profile radar data, a rare severe hailstorm event (1-3 cm in diameter) in Southwest Hubei at the end of winter is analyzed in detail. The results show that the severe hailstorm was produced under the circulation background of upper cold-dry and lower warm-wet and low-altitude convergence and high-altitude divergence. Convective weather was triggered by mesoscale convergence on the ground with favourable terrain at the trumpet and intensified by cold front. Strong vertical wind shear in the lower level was favorable for the formed convective strong storm to maintain and strengthen. The severe hails were produced by isolated supercells and dominant supercells in multicells. In comparison, the isolated supercells were larger and persisted longer. The structures of the supercells reflected typical features such as mesocyclone， high mass center, low-level inflow, weak echo zone and echo drape, middle-level radial convergence and storm-top divergence, etc. The vertically integrated liquid （VIL） and the VIL density maintained high above 35 kg·m-2 and 4 g ·m-3 for a long time in the winter. The hail index of radar algorithm predicts the severe hail with high probability. This process occurred at the end of winter. The typical storm structure showed up after the emergence of convection, and the early warning of hail could be made 10-30 minutes in advance. However, for the short-time potential forecast of severe hail several hours in advance before the occurrence of severe convection, the key parameters (such as CAPE， 0-6 km vertical wind shear and melting layer height) for judging the potential of severe hail are not typical, which will mislead forecasters to ignore the hail potential judgment. Forecasters need to be extremely cautious and do in-depth analysis when conducting potential analysis of severe convective weather in this environmental background, so as to obtain correct forecast results.