1989年7月川东大暴雨中尺度对流系统分析

使用气象卫星资料，分析了１９８９年７月发生在四川东部的４个中尺度对流系统的特征，第一个系统是由３个对流云团合并而成，生成后快速向前移动，第二个为向后传播。第三个系统生成后，系统的西南部不断生成新的对流单体，使之维持准静止状态，最后一个系统的初期呈胞状结构，后与冷锋结合，成为冷锋云系的一部分，这４个系统都是西南低涡暖切变形势下的产物，随着形势演变，其大尺度环境略有差异。

The Analysis of the Mesoscale Convective Systems of the Heavy Rain in Eastern Sichuan Province in 1989

he characteristics of four mesoscale convective systems generated in the eastern Sichuan Province are analysed. The first system was merged from three cloud clusters,and then moved forward rapidly.The second one moved backwark. In the early stage of third system,there were many new convective cells generated continuously in the southwest part of system. Therefore, the system was quasi-stationary. The last system presented cellular structure in the early stage, then it merged with cold front and became a part of the cloud system. All of the four mesoscale convective systems were generated under the condition of the southwest vortex with a warm shear,and their environment flow fields were slightly different.