摘要
利用常规观测、地面加密自动站、多普勒天气雷达观测资料以及NECP(1°×1°)逐6 h再分析资料对2016年8月16日内蒙古东南部地区由于超级单体风暴诱发的强冰雹、雷暴大风等强对流天气进行了分析。结果表明:这次超级单体风暴发生在高空东北冷涡和低层暖式切变线形成的强不稳定层结背景下,低层丰富的水汽、中等强度对流有效位能和大的深层垂直风切变,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露点锋两种对流系统耦合并加强是对流风暴的触发机制;雷达回波有钩状回波、弱回波区WER (Weak Echo Region)、回波悬垂、回波墙、中气旋等超级单体风暴特征,其中弱回波区,回波悬垂由反射率因子从低到高向低层入流一侧倾斜且回波强度梯度大;风暴内中层维持较深厚的气旋性辐合,风暴顶则表现出明显的气旋性辐散特征,标志大冰雹的三体散射长钉TBSS(Three-Body Scatter Spike)特征回波,50 dBZ以上的反射率因子核心的高度伸展到-20℃以上,为典型的产生冰雹的回波结构;垂直液态水含量VIL(Vertical Integrated Liquid Water Content)与风暴顶高之比即VIL密度达到5 g·m^(-3),这也是大冰雹的预报指标。
Based on the conventional observational data,automatic weather station data,Doppler radar data and NCEP(1°×1°) every six hours reanalysis data,the strong convective weather such as strong hail and thunderstorm wind induced by super cell storm in southeastern Inner Mongolia on 16 August 2016 was analyzed.The main conclusions are as follows: The super cell storm occurred in the background of strong unstable conditions caused by the northeast cold vortex in the high altitude and the warm-wet shear line in the lowlevel.The rich water vapor in the low level,medium intensity of CAPE and large deep vertical wind shear provides a very favorable environmental condition for the strong convective weather.The coupling and strengthening of the surface meso-scale convergent line and dewpoint front is the trigger mechanism of convective storm.The features of a supercell storm can be found,such as the hook echo,WER,overhang echo,echo wall,and mesocyclone in the reflectivity products.Besides,the WER and overhang echo have large intensity gradient,which is tilting toward low-level inflowside from lowto high; The mid-level of the storm maintained a relatively strong cyclonic convergence,and the top of the storm showed significant cyclonic divergence.TBSS(Three-Body Scatter Spike)exists and the core of reflectivity above 50 dBZ extends above-20 ℃,which is a typical echo structure of hail.The ratio of the VIL(Vertical Integrated Liquid Water Content) and the top height of the storm which means the density of VIL reaching to 5 g·m^-3 that also a predictor of hail.
作者
张桂莲
常欣
黄晓璐
訾耀海
李瑞青
梁凤娟
ZHANG Guilian;CHANG Xin;HUANG Xiaolu;ZI Yaohai;LI Ruiqing;LIANG Fengjuan(Inner Mongolia Autonomous Region Meteorological Observatory,Huhhot 010051,Inner Mongolia,China;Inner Mongolia Chifeng Meteorological Bureau,Chifeng 024000,Inner Mongolia,China;Inner Mongolia BaYanNaoEr Meteorological Bureau,LinHe 015000,Inner Mongolia,China)
出处
《高原气象》
CSCD
北大核心
2018年第5期1364-1374,共11页
Plateau Meteorology
基金
内蒙古自治区气象局预报员暴雨创新团队项目