2011年4月中旬华南一次超级单体风暴过程分析

摘要

A supercell storm process occurred in Southern China on April 17,2011 was analyzed based on the conventional observation data and WRF model simulation outputs. The results showed that this process was triggered by the combined action of 850 hPa shear line and the surface front. The interaction between high level positive potential vorticity cold air decling along the inclinedθse surface and the low level warm-moist air, which aroused significant convergence and ascent movement area to promote the development of the strong convective. The new supercell was continuously generated in the right front of the former suppercell and maintained longer life of severe convective, which presented a southeast movement.%利用常规资料和WRF模式计算的结果，对2011年4月17日华南地区一次超级单体风暴过程进行综合分析。结果表明，此次强对流发生在高空槽、切变线配合地面锋面的天气背景条件下，切变线和地面锋面共同作用触发了强对流天气的发生；沿倾斜的等θse面下滑的高层正位涡冷空气与低层暖湿空气相互作用，产生明显的辐合上升区，促使强对流不断发展；新的超级单体在原有单体的右前方不断生成，从而维持了强对流较长的生命史，使得超级单体风暴在移动过程中呈现东南向移动的特点。