朔州市“8·12”暴雨分析

Analysis of ‘ 8.12’ rainstorm in Shuo Zhou City

利用MICAPS系统资料对2005年8月12日发生在山西朔州市北部的暴雨天气过程的大尺度环流背景和物理量场进行分析。结果表明:这次暴雨天气过程发生在纬向环流向经向环流调整的过程中,西太平洋副热带高压有一次明显的西伸北抬,是一次典型的副高西北侧西南气流型暴雨。降水水汽主要来自南海,中低层的水汽输送十分充沛,并在朔州市北部形成辐合。低空急流的建立,为此次强降水提供了丰富的水汽和位势不稳定能量;过程期间,物理量场表现出强水汽输送辐合及上升运动;冷空气与暖湿气流及特殊地形的综合作用激发出中尺度降水云团,造成此次强降水。

Analysis of the large scale circulation and physical field of August 12, 2005 rainstorm weather process has been done based on the MICAPS data System. It shows that the rainstorm occurred when the latitude circulation changing into longitude circulation, the subtropical high obviously move to western and northern part, and it is an classical airstreams rainstorm in the Northwest part of subtropical high. Water vapor largely comes from South China Sea, flush water vapor in the middle and lower part converged in the North of Shuo Zhou City. The establishment of Low Jet supply flush water vapor and unstable potential energy. There is strong water vapor transport and convergence upward movement in the physical field. And the compound affection of cold air, warm and wet flow and special terrain lead to the rainstorm.