The rain gush associated with the Jiang-Huai Mei-yu front occurred on July 9,1991, was observed with the Doppler radar in Nanjing Institute of Meteorology. The analysis of the data has shown in this paper that the rain gush was closely related with the activity of the mesoscale vortex system in the boundary layer. The vertical structure features of air flow in the lower atmosphere in the region are also revealed.