According to the rainfall data of 10 sites in Tongren from 2013 to 2017,Select regional rainstorm cases from May to July,Using regular weather data and NECP data,Summarizing the main impact systems of heavy rains,The circulation characteristics and physical quantity characteristics of cold low vortex shear storm and warm low vortex shear storm are compared and analyzed.Analysis found that:①The circulation characteristics of cold low vortex shear storm are:The 500hPa high altitude subtropical high ridge line is stable.Multi-fluctuation groove,There are obvious low vortex shears in the middle and lower layers.The low vortex center is in the area of Sichuan and Chongqing.Eastward path;There is no obvious front on the ground.There is weak cold air penetration,Mostly based on the northerly path,No significant cooling;Its frequency is 33% of low vortex shear storms.It is mainly from May to June.②The circulation characteristics of warm low vortex shear storms are as follows:The 500hPa high altitude subtropical high ridge line is stable.There are obvious low vortex shears in the middle and lower layers.The 850hPa low vortex is mostly located above the Tongren.Move eastward to the south;The ground is mostly a pressure equalization field.At the bottom of the warm and low pressure,The rear part of the sea;Its frequency is 67% of low vortex shear storms.It is mainly from June to July.③The physical characteristics of cold and warm low vortex shear storms are as follows:The water vapor condition is the largest during the rainstorm period.Decrease at the end;Dynamic conditions and thermal conditions and k-index gradually increase in two periods before and during the occurrence of heavy rain (maximum occurrence),Decrease after occurrence;Other unstable energy conditions are irregular;The occurrence of heavy rain is not related to unstable energy.