摘要
利用常规探测资料、NCEP再分析资料、S波段多普勒雷达资料等,对2019年7月6日发生在宿迁市的一次强飑线天气过程进行综合分析。结果表明:该次强飑线天气过程是在深厚的东北冷涡背景下发生的。飑线回波在移动过程中“弓”状特征愈发明显,后侧入流缺口、中气旋及速度模糊的出现,预示着地面极端大风的发生;回波垂直剖面上存在一个有界弱回波区,中高层有回波悬垂。在飑线发展过程中,近地面层风场垂直梯度增大,风切变迅速增强,有利于对流风暴的组织化和飑线的维持。对流层中低层存在一稳定层结,有利于低层能量的累积,随着冷中心南移,干冷空气叠置于低层暖湿气流之上,引发上升运动,突破了大气稳定层结,强对流暴发。
Based on the conventional observations,NECP reanalysis data and S-band Doppler radar data,this paper analyzes the weather process of a strong squall line on July 6,2019 in Suqian City.Results show that:The strong squall line weather process occurred in the background of a cold vortex activity in Northeast China.The bow like characteristics of squall line echoes are more and more obvious on the move.The appearance of rear inflow notches,mesocyclones and velocity ambiguity indicates the occurrence of extreme gale on the ground.There are bounded weak echo regions and overhang echoes on the vertical cross-section.In the process of squall line development,the vertical gradient of wind speed in the surface wind and the wind shear increases rapidly,which is conducive to the organization of convective storm and the maintenance of squall line.There is a stable stratification in the middle and lower troposphere,which is conducive to the accumulation of energy in the lower troposphere.As the cold center moves southward,the dry and cold air overlaps on the warm and wet air flow in the lower troposphere,leading to upward movement,breaking through the stable stratification between the atmosphere and causing strong convection.
作者
徐恩
庞礴
程昕
周航
王锦杰
张莹
XU En;PANG Bo;CHENG Xin(Suqian Meteorological Bureau,Suqian,Jiangsu 223800)
出处
《安徽农业科学》
CAS
2020年第17期225-228,268,共5页
Journal of Anhui Agricultural Sciences
关键词
飑线
强对流
冰雹
大风
Squall line
Severe convection
Hail
Gale