吉安市2019年7月7-9日连续暴雨过程分析

Analysis of Continuous Rainstorm Process in Ji’an City from July 7 to 9,2019

2019年7月7—9日吉安市出现连续暴雨过程,给农业生产造成较严重的损失。利用NCEP再分析资料、常规观测资料和雷达资料,重点分析了高低层环流形势、雷达回波图和物理量场,得出暴雨产生的原因。结论表明,此次暴雨过程受高空槽、低空切变和西南气流共同作用形成。高空存在辐散下沉气流,低空存在辐合上升气流,有利于冷暖空气相交;比湿和相对湿度均表明此次过程水汽条件充沛;其对流有效位能和K值均较大,对流条件较好。在雷达回波图上主要为层状积状混合云系的回波,且呈现出列车效应。

From July 7 to 9,2019,a continuous rainstorm occurred in Ji’an City,causing serious losses to agricultural production.In this paper,NCEP reanalysis data,conventional observation data and radar data are used to analyze the circulation situation of high and low layers,radar echo pattern and physical quantity field,so as to obtain the cause of rainstorm.The conclusion shows that the rainstorm process was formed by the action of upper-level trough,low-level shear and southwest airflow.There are divergent downdrafts in the upper air and convergent updrafts in the lower air,which are conducive to the intersection of warm and cold air.The specific humidity and relative humidity showed that the water vapor condition was sufficient.The convective effective potential energy and K value are larger,and the convective conditions are better.On the radar echo pattern,it is mainly the echo of stratified and accumulative mixed cloud system,and shows the train effect.