摘要
利用常规资料、地面加密资料、雷达等资料,对2017年4月5日贵阳一次飑线天气过程进行中尺度特征和雷达分析,结果表明:(1)本次强对流天气过程是高空槽和低层切变线共同影响的有利形势下产生的,"上干冷,下暖湿"的不稳定层结条件下,地面辐合线触发机制,导致不稳定能量的释放。(2)中尺度辐合中心有利于飑线生成和发展,造成此次强天气过程的对流风暴,其位置和走向与地面辐合线基本一致。(3)飑线是造成清镇大风及贵阳主城区冰雹的主要原因,地面大风主要产生在温度梯度最大区域靠暖区一侧。(4)飑线回波特征中的高悬的强回波、有界弱回波区、回波悬垂、回波墙、飑线后侧伴有入流急流等特征对冰雹天气有较好的指示意义。飑线回波前沿的反射率因子梯度大,强回波质心高度下降、后侧伴有入流急流、中层径向辐合等特征对大风预报具有一定的预示作用。
The features of a squall line weather process on April 5 in Guiyang was analyzed based on conventional data,surface observation data,radar data. Results show that：（ 1） The strong convective weather was caused by the high-level trough and low-level shear. The air with upper-layer dry and lower warm is unstable,resulting in the release of unstable energy with surface convergence line trigger mechanism.（ 2） The mesoscale convergence centers position moving have produced basically consistent with surface convergence line,advantageous to squall line development.（ 3） The squall line is mainly reason of fresh gale in Qingzhen and the hail of Guiyang.The surface wind mainly occurs at the maximum temperature gradient and depends on the side of the warm zone.（ 4） The strong echo,bounded weak echo area,echo draping,echo wall and squall line with the characteristics of incoming jet stream which has a good indication for hail weather. The front of the squall line engender fresh gale,reflectivity factor gradient varies,strong echo centroid height decrease,jet flow run behind,the middle radial convergence which are characterized as a predictive role of gale forecasting.
作者
王君军
王彪
周博扬
WANG Junjun;WANG Biao;ZHOU Boyang(Guiyang Meteorological Observatory,Guiyang,550001,China;Guizhou Meteorological Bureau,Guiyang,550002,China)
出处
《中低纬山地气象》
2018年第2期36-40,共5页
Mid-low Latitude Mountain Meteorology
基金
贵阳市气象局气象科研基金(筑气科合201707号)资助
关键词
强对流
地面辐合线
超级单体
飑线
convection
surface convergence line
supercell
squall line
