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Based on the data of the ground automatic station, Doppler weather radar, satellite hourly TBB data and NCEP reanalysis data, two strong convective weather processes (the process of 21-22 and the process of 26-27) in late March 2020 are compared and analyzed. The results show that: (1) The two strong convective weather processes had good coordination of dynamical, thermal and water vapour conditions. The circulation configuration of high-level divergence and low-level convergence was conducive to upward movement. The strong development of thermal unstable stratification, coupled with favourable water vapour conditions, triggered by systems such as the upper trough and the surface convergence line, led to the occurrence of mixed strong convection weather. (2) The two strong convective weather processes were divided into two stages, namely, warm advection forced strong convection and baroclinic frontogenesis. The accumulation of unstable energy was obvious in the forced phase of warm advection, and it was released to a certain extent before the beginning of the baroclinic frontogenesis phase. The dynamical conditions and water vapour convergence in the baroclinic frontogenesis stage of the two processes were stronger than those in the warm advection stage. (3) Hail, thunderstorms, gale and short-term strong precipitation occurred in the two strong convection weather processes. In the first process, the southwest jet developed more vigorously, the intensity of the warm advection centre was stronger, the vertical extension height was thicker, and the thermal conditions were better, mainly thunderstorms, gales and hail. In the second process, the cold air was stronger, and the significant upward movement lasted longer, with a more abundant water vapour supply, mainly short-term strong precipitation. (4) Hail occurred in 19:00-20:00 in Guanzhuang Town, Yuanling County, Huaihua, in both processes. The radar echoes all reflected the typical hail echo characteristics. The maximum reflectivity factor of the “21-22 process” was larger than that of the “26-27 process”, the intensity of the mesocyclone was stronger, the vertical cumulative liquid water content (VIL) jump was more obvious, and the value was larger, the expansion height of the mesocyclone was higher, and the upper air divergence was stronger, so the diameter of the hail was larger.