一次雷暴回波短带产生强天气的特征分析

Analysis of the Characteristics of Strong Weather Produced by a Short Band Thunderstorm Echo

为了研究雷暴回波短带在强降水和雷暴大风事件中的特征,使用地面气象要素、闪电信息、MICAPS天气图、雷达拼图等资料,对2023年5月17日江西中北部出现的雷暴回波短带进行分析,结果表明:1)雷暴回波短带发生在200 hPa“出流区”、500 hPa槽前西南气流低涡发展、850 hPa低涡切变线西南气流大气环流中,地面低气压和辐合线发展,为午后雷暴回波短带的形成提供了触发机制。2)雷暴回波短带在雷暴发展初期,通常呈现出不是很强的回波和较弱的闪电活动;在低涡回波团后侧地面辐合线附近发展。随着时间的推移,回波强度快速增强发展,闪电开始增多。3)雷暴回波短带特征包括回波强度较强(50~55 dBZ)、回波顶较高(10~12 km左右)、回波带较短(相比冷锋回波带和飑线回波带),影响区域较小,持续时间较短和短带上回波单体强度分布不均匀等。4)强降水的垂直积分液态水含量(VIL)在20~25 kg/m^(2)附近,而一般降水的VIL都在10 kg/m^(2)以下。因此,在雷暴天气监测和预报中需要综合多种资料分析,以更好地预测强降水和雷暴大风事件的发生。

In order to study the characteristics of short thunderstorm echo bands in heavy rainfall and thunderstorm gale events,the data of ground meteorological elements,lightning information,MICAPS Weather map,radar mosaic,etc.were used to analyze the short thunderstorm echo bands in the central and northern Jiangxi on May 17,2023.The results showed that:1)the short thunderstorm echo bands occurred in four weather features,the“outflow area”of 200 hPa,the southwest airflow vortex development in front of the 500 hPa,the southwest airflow Atmospheric circulation of 850 hPa vortex shear line,the development of Low-pressure ground area and convergence line,provided a trigger mechanism for the formation of short thunderstorm echo bands in the afternoon.2)In the early progress stages of thunderstorm,the short band of thunderstorm echoes usually exhibited weak echoes and lightning activity;It developed near the ground convergence line behind the low vortex echo cluster.With the passage of time,the intensity of the echoes increased rapidly and lightning began to increase.3)The characteristics of thunderstorm echo short band include strong echo intensity(50~55 dBZ),high echo crest height(about 10~12 km),short echo band(compared with cold front echo band and squall line echo band),small impact area,short duration and uneven distribution of echo unit intensity on the short band.4)The vertical integral Liquid water content(VIL)of heavy rainfall was about 20~25 kg/m^(2),compared with the VIL of general precipitation was Below 10 kg/m^(2).Therefore,in thunderstorm weather monitoring and forecasting,it is necessary to analysis multiple data to predict the heavy precipitation and strong winds thunderstorm better.