Abstract: This paper uses multi-source observation data such as the new generation FY-4A satellite and GPM satellite precipitation radar to select two heavy rain cases where the plateau vortex interacts with the southwest vortex, and analyzes the mesoscale precipitation cloud system in the basin under the action of the two vortices.Spatial structure characteristics.The results show that the coupling of the southwest vortex and the plateau vortex produces a mesoscale convective complex MCC cloud system.Shortterm heavy rainfall mainly occurs during the mature stage of MCC, and the cloud top brightness value of the large area covered by the heavy rainfall area is lower than -60℃, The height of the cloud top is about 12 km; when the southwest vortex interacts with the plateau vortex, the center position and intensity of the low brightness temperature area of the cloud top correspond well to the characteristics of the simultaneous strong precipitation; the reflectivity factor of the convective precipitation particles in the precipitation cloud is The low-level rapid growth, the area where the intensity of the reflectance factor of stratiform precipitation particles increases is near the zero-degree bright zone; the rain intensity of convective precipitation is much greater than that of stratiform clouds, and its particle radius is also greater than that of stratus precipitation, while the concentration of convective precipitation particles Higher than or equal to the latter; Stratus clouds contribute more to total precipitation than convective clouds, and stratus precipitation shows the result of particle accumulation of uniform size; Convective precipitation rate is vertically distributed in a columnar shape with cloud walls, stratiform The vertical distribution of precipitation rate is irregular columnar and there is no significant cloud wall.The precipitation rate decreases with the increase in altitude.The troposphere below 5 km contributes the most to the total precipitation.