气象2023，Vol.49Issue(11)：1315-1327,13.DOI:10.7519/j.issn.1000-0526.2023.083001
多个超级单体风暴诱发的EF3级强龙卷特征分析
Characteristic Analysis of EF3 Strong Tornado Induced by Multiple Supercell Storms
摘要
Abstract
In Taipusi Banner of Xilin Gol League,Inner Mongolia,a rarely-seen EF3 strong tornado oc-curred on 25 June 2021,resulting in 6 deaths and a large number of buildings'damage and other losses.Based on meteorological observation data,automatic weather station data,CB-Doppler radar observation data of Zhangbei,Hebei Province,FY-4 satellite data and NCEF FNL(1°× 1°)6 h reanalysis data,this paper comprehensively analyzes the process of the strong tornado.The results show that this tornado oc-curred in the background of unstable stratification environment of the forward-tilted trough.The strong conditional instability in the middle and low troposphere(the vertical temperature lapse rate at 850 hPa and 500 hPa was about 7.7 ℃·km-1),abundant water vapor in the lower layers,medium-strength convective available potential energy,and strong 0-6 km vertical wind shear provided favorable environmental condi-tions for supercell storms and tornadoes.In addition,the 0-1 km vertical wind shear was 8 m·s-1,and the lifting condensation height was 1.0 km,which provided relatively favorable environmental conditions for the occurrence of supercell storms and tornadoes.The convergence line accompanying the ground dry line triggered the parent storm that produced the tornado,and then evolved into the supercell.The radar reflectivity factor showed the characteristics of a typical hook echo,the inflow gap of warm and wet air at low level,the weak echo region at low level,the overhang echo at middle and high level,and the moder-ate-strength mesocyclone,etc.In the process of the formation and extinction of the tornado,three super-cell storms formed successively,and all of them appeared in the isolated convective storm form.The torna-do occurred at the top of one of the supercells,which was the junction of the front updraft and the rear downdraft.The possible start time and path of tornado based on the evolution of mesocyclone intensity an-alyzed by radar are in good agreement with the time of field investigation.Except for the strong tornado,this series of supercells also produced large hail and linear convection gale(thunderstorm gale),the strong echo center was significantly tilted from low to high,and the maximum reflectivity factor was as high as 65 dBz.In addition to the moderate-strength mesoclones,there was also obvious mid-level radial conver-gence in the diagram of radial velocity.At the time of supercell storm formation,the vertical integrated liquid water content(VIL)was as high as 73 kg·m-2,the VIL density was 4-5 g·m-3.These radar echo characteristics indicate the existence of large-sized hail,while the mid-level radial convergence was the radar echo characteristic of thunderstorm gale.关键词
强龙卷/超级单体风暴/中气旋/"V型"缺口/钩状回波/大冰雹Key words
strong tornado/supercell storm/mesocyclone/V-shaped notch/hook echo/large-sized hail分类
大气科学引用本文复制引用
张桂莲,李一平,江靖,常欣,霍志丽,仲夏,郭炳瑶,贾克寒..多个超级单体风暴诱发的EF3级强龙卷特征分析[J].气象,2023,49(11):1315-1327,13.基金项目
内蒙占自然科学基金项目(2020MS04020)、中国气象局东北冷涡科研业务能力提升攻关团队共同资助 （2020MS04020）
