2019年柳州盛夏一次大暴雨灾害过程成因分析

Cause analysis of a heavy rainstorm in midsummer of 2019 in Liuzhou

利用柳州市气象站资料、micaps资料、雷达资料及ncep再分析数据对2019年6月22~23日柳州市大暴雨天气过程进行综合分析,结果表明此次过程各层系统配合较好,高层辐散、高空槽东移、低层切变线、低空急流和超低空急流相配合以及地面冷锋触发,共同导致大暴雨过程发生,该过程与水汽条件、不稳定条件、动力条件等物理量场均具有较好对应关系。同时,地形对降水过程起到一定增幅作用,过程为明显飑线影响过程,列车效应明显,维持时间较长,飑线后部层状云降水明显,导致暴雨过程发生。

Based on the data of Liuzhou meteorological station,MICAPS data,radar and NCEP reanalysis data,this paper makes a comprehensive analysis of the heavy rain weather process in Liuzhou from June 22 to 23,2019,The results show that all layers of the system cooperate well,The high-level divergence,the eastward movement of the high-level trough,the low-level shear line,the combination of the low-level jet and the ultra-low-level jet,and the triggering of the ground cold front all led to the occurrence of the heavy rain.The process has a good correspondence with water vapor,instability and dynamic field.At the same time,the topography plays a certain role in increasing the precipitation process.This process is an obvious squall line influence process,the train effect is obvious,the maintenance time is long,and the stratiform cloud precipitation behind the squall line is obvious,which leads to the rainstorm process.