2005年6月华南持续性暴雨爆发和维持机制分析

A Study of the Explosive and Maintaining Mechanism of Persistent Heavy Rainfall during the June 2005 in South China

利用常规气象资料及T213分析场资料，对2005年6月18日～23日华南大范围持续性暴雨过程的高低空形势、能量及动力条件进行诊断分析。发现：这次过程低空急流维持了低空对流不稳定形势，高空急流维持了高空辐散、低空辐合的有利形势，高空西南急流与高空西北急流一样，能造成暴雨区高空有利的辐散形势，形成高层辐散、底层辐合，触发强烈的上升运动，高低空耦合是此次强降雨爆发的熏要机制，强降雨落区位于低空西南风急流出口区的左侧和200hPa西北风急流的出口区西南侧，即低空急流的左侧与切变线的前沿；暴雨区域高湿能条件的维持．保证了强降雨过程的能量供给，是强降雨持续的重要条件。

Based on the observational data and T213 analysis data , by diagnosing the weather situation , energy and dynamic conditions , the features of persistent torrential rain in south China from 18 to 22 June, 2005 are conducted. Results show that the LLJ makes the convective instability and the upper jets, including SW jet and NW jet keep the convergence at low level and divergence at high level, which give rise to the strong vertical movement. The interaction of the LLJ and ULJ is the important mechanism of the outbreak of the heavy rain. The strong rainfall take place around the left exit of the LLJ and the right of the northwesterly upper jet at 200hPa. High moisture and energy keeps the rainfall maintaining and strengthening.