一次MCS过程的特征分析

Characteristic analysis on a MCS process

对2010年9月7—8日江苏北部的中尺度对流系统(MCS)特征和暴雨过程进行了分析,应用卫星云图、热力和动力物理量诊断。结果表明:MCS是由若干个α和β中尺度对流云团组成,在MCS成熟阶段有一个逐渐发展成中尺度对流复合体(MCC)的过程;MCS出现在高温高湿对流不稳定的环境中,低层低涡的辐合和锋面的抬升作用为其提供了动力条件;强水中心与MCS云顶温度梯度最大值中心相对应,为暴雨落区预报提供了着眼点。

Using physical quantity diagnostic analysis, this paper analyzes, a MCS and the rainstorm process occurred on 7 and 8 September 2010 in the north of Jiangsu province and explores the characteris- tics of MCS as well as the relationship between the MCS and rainstorm process. The results show that the MCS was composed of several meso-β-scale and meso-et-scale convection clusters： in the mature stage of MCS, there was a gradual development towards the process of mesoscale convective complexes （MCC）. MCS occurred in the environment with high temperature, considerably wetness and unsteady convective stratification in the air. Surface cyclone development in cooperation with the convergence and the role of the front of the uplift had provided dynamic conditions for MCS. It is also indicated that the precipitation centre corresponded with the maximum gradient of the cloud top temperature very well, so that it can pro- vide reference for the forecast of downpour weather and its area.