Abstract: The mean cloudiness distribution of the severe rainfall over the Jiang-Huai area in summer of 1991 is described by processing the infrared data of GMS-4 geostationary satellite. In basis of the GMS-4 hourly image animations and 3-hour interval images for the six severe rainfall events in June of 1991, the evolutionary images of the three kinds of cloud types for the interaction of middle-low latitude cloud system during the Mei–yu period are presented. Also, the features of water-vapour transportation are studied based on the TOVS water-vapour retrievals processed and θse field in the lower troposphere for the severe rainfall.