Abstract: [Abstract]The paper aims to improve typhoon torrential forecast accuracy, reduce agricultural losses caused by typhoon rainstorm,and provide decision basis for disaster prevention and reduction.Using NCEP 6-hourly reanalysis data with resolution 1°×1°, regional automatic weather station live observation data and combined with terrain features ,the authors analyzed the causes of heavy rainfall in Zhejiang by “Soudelor” from typhoon track,physical field which are related to heavy rainfall,near the surface layer of the convergence and the effect of terrain.The results shows that The interaction between the typhoon track and the large scale circulation is closely related.Further,the positive vorticity field axis also indicates the future trend of the typhoon to some extent.In this case,”Soudelor” had a long time maintenance to moving northwest before landing is mainly due to the stability of the subtropical high.By analyzing the relationship between strong precipitation and each physical quantity field, the following conclusions can be drawn:(1)Typhoon torrential rain is always in the junction area of the southeast jet and the mountain wind slope.(2)The heavy rainfall have some correspondences between moisture flux convergence area,high value of specific humidity area,high value of positive vorticity area and the twin peaks of pseudo equivalent temperature.In addition,the long time maintenance of near the surface layer convergence system,the east low west high terrain of Taizhou and the local bell shaped terrain are important conditions for the local production of super precipitation.