2021年湘潭初春一次强降雨成因分析

Analysis of the Causes of a Heavy Rainfall in Xiangtan Early Spring in 2021

利用高空、地面常规观测资料,NCEP格点再分析资料和多普勒雷达资料,分析湘潭早春的一次强降水过程形成原因。结果表明:(1)暴雨发生时,中低空的急流发展旺盛,850 hPa、700 hPa切变线位置重合(2)地面有低压倒槽发展,地面辐合线是主要的触发系统。(3)高层辐散对应低层辐合,有利于上升运动。(4)东西向的强对流回波排列成行,以“列车效应”形式造成湘潭北部强降雨。

Using high-altitude and ground routine observation data,NCEP grid reanalysis data and Doppler radar data,the reasons for the formation of a heavy rainfall in Xiangtan in early spring were analyzed.The results show that:(1)When a heavy rain occurs,the mid-to-low-altitude jet stream developed vigorously,and the positions of the 850 h Pa and 700 h Pa shear lines coincide.(2)There was low-pressure inverted trough development on the ground,and the ground convergence line was the main trigger system.(3)Highlevel divergence corresponds to low-level convergenced,which was conducive to upward movement.(4)The strong convective echoes in the east-west direction were arranged in rows,causing heavy rainfall in the northern part of Xiangtan in the form of“train effect”.