摘要
利用地面观测资料、探空资料以及石家庄多普勒天气雷达和饶阳双偏振雷达资料等,对2018年6月13日影响河北中南地区的一个长生命史超级单体风暴的环流背景、雷达观测特征等进行了分析。结果表明:(1)此超级单体发生在涡后横槽转竖的环流背景下。(2)风暴生命史长204 min,其中超级单体维持时间长达138 min,其间雷达最大反射率因子基本上维持在65 dBz以上。(3)中气旋深厚并强烈发展是超级单体发展和维持的重要动力机制。中气旋底高最低可达风暴底部,顶高变化幅度较小,低质心中气旋和高质心中气旋的形成和发展都可能引起地面降雹,降雹期间对应超级单体短暂减弱。(4)超级单体维持期间一直伴有气旋、反气旋涡旋对特征。超级单体的钩状回波特征明显,表现为典型的回波墙-弱回波区-悬挂回波的垂直结构;低层辐合、高层辐散,高空辐散大于低层辐合,有利于超级单体内部强烈的旋转上升运动;有明显的三体散射和旁瓣回波,三体散射最长超过60 km,持续时间长达150 min。(5)双偏振雷达探测的超级单体反射率因子≥55 dBz,对应位置差分反射率-0.5~0.5 dB,差分传播相移率仅1.5~2.0°/km,相关系数在0.75~0.92之间,表明超级单体内同时存在液滴和较大冰雹。
Using datasets of routine upper-air and surface weather observations,surface automatic weather station,Doppler weather radar at Shijiazhuang,dual-polarization radar at Raoyang and other relevant data,we have conducted a detailed analysis on the atmospheric circulation environment and radar observed characteristics of a supercell storm with long life cycle that affected the central and southern Hebei on 13 June 2018.The main results are as follow.(1)This supercell occurred under the atmospheric circulation of the revising of a transverse trough at the back of vortex.(2)The life cycle of the storm is 204 min long,during which the supercell lasted for 138 min,and the maximum radar reflectivity factor is basically maintained above 65 dBz during this period.(3)The deep and strong development of a mesocyclone is an important dynamic mechanism for the development and maintenance of the supercell storm.The bottom of the mesocyclone can reach the bottom of the storm,and the top height of the mesocyclone had little changes.The formation and development of both low-centroid and high-centroid mesocyclone may cause hail on the ground,and the supercell weakened temporarily during the corresponding hail period.(4)During the maintenance period of supercell,the vortex pairs of cyclones and anticyclones are always accompanied,and the cyclonic vortex is dominant.The hook echo characteristics of the supercell are obvious,which shows the typical vertical structure of echo wall-weak echo region-hanging echo.The structure such as convergence in the low-level,divergence in the upper level,and divergence in the upper level being greater than convergence in the low-level,is conducive to the strong rotation and ascending movement within the supercell.There are obvious three body scatter signature(TBSS)and sidelobe echo,and the longest TBSS is more than 60 km and its duration is as long as 150 min.(5)Dual polarization radar detection shows that the reflectivity factor of the supercell is greater than or equal to 55 dBz,the differential refl
作者
陈瑞敏
赵孝伟
于海磊
王丛梅
CHEN Ruimin;ZHAO Xiaowei;YU Hailei;WANG Congmei(Hengshui Meteorological Office of Hebei Province,Hengshui 053000;Hebei Key Laboratory of Meteorology and Ecological Environment,Shijiazhuang 050021;Xingtai Meteorological Office of Hebei Province,Xingtai 054000)
出处
《暴雨灾害》
2021年第4期419-429,共11页
Torrential Rain and Disasters
基金
河北省“十三五”气象重点项目(hbrywcsy-2017-05)
国家重点研发计划(2017YFB0504002)
河北省自然科学基金项目(D2020108049)
河北省衡水市气象局科研开发项目(18hsky03)。
关键词
超级单体
中气旋
涡旋对
冰雹
雷达回波特征
supercell storm
mesocyclone
vortex pairs
hail
radar echo characteristics
