本文利用济南CINRAD/SA雷达的探测资料对2005年7月12日发生在山东境内的一次弓状回波和超级单体过程分析表明,这次弓状回波和超级单体产生在东北低涡横槽转竖及真潜在不稳定的天气形势下。雷达本站的风廓线清楚揭示了横槽转竖前后的高空风场变化,对强对流天气的临近预报具有指示意义。横槽转竖时弓状回波产生,反射率因子图上后侧入流槽口的出现是弓状回波即将形成的前兆信号。一个典型超级单体产生在弓状回波头部前方的暖区中,二者相互作用合并后强度加强。弓状回波具有持续产生中气旋的能力。中气旋多出现在其头部和颈部的前沿,绝大部分中气旋产生冰雹和大风等灾害性天气。
Bow echo and supercell interaction occurred on 12 July 2005 in Shandong province is analyzed based on Jinan CINRAD/SA radar data. The results show that bow echo and supercell appeared when the horizontal trough turned to longitudinal one and atmosphere is unstable. Wind-profiler products reveal clearly the change of high wind before and after the horizontal trough turning to longitudinal trough. Emergence of rear-inflow notch in base reflectivity map is the signal for bow echo form ation. Typical supercell occurs in the warm area in front of the head of bow echo. They all tend to strengthen after combination. Bow echo can lead to mesocyclones continually. What's more, most of mesocyclones bring hail and strong convective wind gust.