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Two severe convective weather events (processes “3〖DK〗·21” and “4〖DK〗·9”) in Jiangxi Province in the spring of 2019 are compared and analyzed, by using conventional meteorological observation data. The results show that: (1) Both strong convection processes were formed by the cold air entering the inverted trough. In the “3〖DK〗·21” process, the convergence of cold and warm air was obvious, the temperature trough was ahead of the height trough, and the jet wind speed presented convergence characteristics. During the“4〖DK〗·9” process, the front convergence was weak, and the cold front moved faster. (2) During the “3〖DK〗·21” process, the wet layer was deeper, the high value potential vorticity pool in the upper troposphere extended from top to bottom till 400 hPa, and the “dry invasion” feature was obvious. During the “4〖DK〗·9” process, the overall humidity condition in the middle and lower troposphere was poor, and there was obvious dry air involved in the middle and upper troposphere, while the strong downdraft caused by cooling evaporation caused the ground gale. (3) During the “3〖DK〗·21” process, the bowecho feature was obvious, and the number of mesocyclones was up to 9. The cold air intruded from the height of 3 km and transferred momentum rapidly, and moved faster, which had an indicative significance for the early warning of severe convection such as gales. The invasion of cold air was shallow during the “4〖DK〗·9” event, VIL (Vertical Integrated Liquid water content) of the single storm was small, and strong wind was possibly underestimated by nowcasting warning.