通辽地区一次短时强降水特征分析  

Analysis of the Characteristics of a short-term Heavy Precipitation in Tongliao Area

作　　者：齐佳慧 王一冰 贾宁 刘梦迪 郭鲁彦[1] Qi Jiahui;Wang Yibin;Jia Ning;Liu Mengdi;Guo Luyan(Tongliao Meteorological Bureau,Inner Mongolia Tongliao 028000)

机构地区：[1]通辽市气象局,内蒙古通辽028000

出　　处：《内蒙古气象》2023年第2期3-7,14,共6页Meteorology Journal of Inner Mongolia

摘　　要：利用常规观测资料、地面加密自动气象站观测资料、多普勒天气雷达观测资料和ECMWF-ERA5再分析资料,对2018年8月28—29日通辽地区的短时强降水、雷电、大风等强对流天气进行分析。结果表明:此次短时强降水天气发生在高空冷涡和低层“人”字形切变线形成的强不稳定的层结背景下,700~850hPa持续的偏南气流为此次暴雨过程提供了充沛的水汽,“上干下湿”的垂直结构配置加剧了对流不稳定性,为强对流天气的发生提供了非常有利的环境条件;地面中尺度辐合线和辐合中心则是此次强降水的主要动力触发机制,小时降水量达到峰值时,地面气象要素突变,极大风速达24.0m·s^(-1);此次短时强降水主要的影响系统为弓形回波复合体(BEC),它是多个对流单体群在移动发展中逐渐合并、断裂再生成的过程,雷达回波中有低质心、弱回波悬垂、单体回波顶高大于8 km、逆风区等特征。Based on the conventional observation data,automatic station data,Doppler weather radar data and ECMWF-ERA5data,the short-time heavy precipitation,thunder and lightning,strong wind and other convective weather during August 28 to 29,2018 in Tongliao area were analyzed.The results show that the short-time heavy rainfall occured under the background of strong and unstable stratification formed by upper cold vortex and lower"human-shaped"shear line.700~850 hPa continuous southerly airflow provided abundant water vapor for this rainstorm process.The vertical configuration of"dry at the upper level,wet at the lower troposphere"aggravates convective instability,which provided a very favorable environment for the occurrence of severe convective weather.The surface mesoscale convergence line and convergence center were the main dynamic triggering mechanism of the heavy rainfall.When the hourly precipitation reached its peak,the surface meteorological elements suddenly changed and the maximum wind speed reached 24 m·s^(-1).The main influence system of the short-time heavy rainfall was the arcuate echo complex(BEC),which was a process that several convective monomer groups were gradually merged and regenerated during the moving development.The radar echo had the characteristics of low mass center,weak echo overhang,monomer echo top height greater than 8km,and the wind reversal zone.

关 键 词：强对流 暴雨 大风 中尺度辐合线 弓状回波 

分 类 号：P458.121[天文地球—大气科学及气象学]