Analysis of Heavy Rainstorm Caused by Parallel Linear Convection System in Early Spring in Southern Anhui
A heavy rainstorm process in the south of Anhui Province in mid-March 2022 was studied using multi-source meteorological data and ERA5 reanalysis data from the European Center.The results showed that under the influence of the stable east Bay Lake trough,the North-west Pacific subtropical high and the eastward strengthening West China evacuation trough,the surface cold front moved southward rapidly,and the mesoscale parallel linear convective system that caused heavy rain formed on the southern windward slope of Dabie Mountain near the sur-face cold front and moved eastward,showing a train effect.The southwest jet,low vortex shear and large vertical wind shear in the middle and lower troposphere provide favorable environmental conditions for its development and maintenance.The complex terrain played an important role in the development and evolution of parallel linear convective system. The mountainous area enhanced the north-south horizontal temperature gradient and continuously generates new updrafts through the convergence of the near-surface wind field on the windward slope or the bell-mouth.After the triggering of the low-level convection,the linear convective system moved northward with the southerly air and presents the characteristics of backward propagation.The whole parallel linear convection moved eastward with the mid-level guiding wind direction.The cen-ter of heavy precipitation in Taihu Lake not only had the convergence of the southeast wind and the southward northeast wind around Dabie Mountain,but also was located at the bell-mouth of the windward slope.The topographic uplift enhanced the cooperation of the radiation,and the convection developed the most vigorously.The dual-polarization radar parameters and raindrop spectrometer showed that there were a large num-ber of dense raindrops over Taihu Lake,and the precipitation efficiency was high.
Heavy rainstormParallel linear convective systemMountainous areaDual polarization radar
万方数据
维普
