Lower-middle-level wind data between 0. 5 and 5. 0 km retrieved using the Doppler radar data 4DVAR, as well as observation data from ground-level,upper-air and regional automatic weather station ( AWS) were used to comprehensively analyze the formation and development of the windstorm during a disaster-causing severe con-vective process occurring on June 8,2016 over Qinhuangdao. The impending early-warning on multi-cell wind-storm was discussed as well. The results show that the stratification conditions with cold and dry air at upper levels and wet and warm air at lower levels favor the formation of severe convective weather. The trigger mechanisms of the process were ground-level convergence lines and dew point fronts,and the sudden changes of wind and temper-ature data from AWS had a good implication for determining the gust front of the storm cell. When the storm cell strengthens into a supercell and is near to the gust fronts,convergence ascending motions caused by outflow and in-flow are mainly located on the edge of the regions where the echo intensities are 15-30 dBz between lower and middle levels in the supercell. Downward airflows always appear in relatively strong echo regions at lower levels, whereas the separations of the ascending and descending motions ensure the long-time development and propaga-tion of the supercell. When the outflow gust fronts are far away from the back of the mature storm,a new convec-tive storm is triggered to form at a distance of about 15. 0-20. 0 km,leading to the backward propagation of the convective system. Through the estimations on the propagation vector motion directions,one can find out the devel-opment regions of the windstorm in advance,with the early-warning time of 30 min. Persistent values of vertically integrated liquid density ( VILd) above 4 g·m-3 are important indicators for the forecast of large hails with the sizes of 2-5 cm.%利用多普勒雷达和4DVAR反演的0.5-5.0 km中低层风场资料及地面、高空、区域自动气象站等观测资料,对2016年6月8日秦皇岛地区一次致灾性强对流天气过程中风暴的生成和发展进行了综合分析,并探讨了多单体风暴的短临预警.结果表明:上干冷、下暖湿的层结条件有利于强对流天气的发生,地面辐合线和露点锋是秦皇岛地区此次强对流天气的触发机制,区域自动气象站风场和温度的突变对风暴单体的出流阵风锋具有指示作用.当风暴加强为超级单体并与阵风锋接近时,在超级单体的中低层(0.5-5.0 km),出流与入流形成的辐合上升运动位于回波强度为15-30 dBz的边缘区域,而低层较强回波区域多为下沉气流,上升和下沉运动的分离确保了超级单体可以维持长时间的发展,出现传播运动;出流阵风锋远离成熟风暴单体后侧,在其后侧约15.0-20.0 km处触发生成新的对流单体,导致对流系统的后向传播运动.通过传播运动矢量方向的估算可以提前预判风暴单体的发展区域,预警时效可以提前30 min,垂直累积液态水含量密度持续大于4 g·m-3对2-5 cm大冰雹的预报具有重要指示作用.
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