中文摘要：

借助加密观测资料、雷达组网拼图资料、雷达风场反演资料以及模式模拟资料等，采用综合诊断方法集中研究2008年6月5-7日发生在广东和广西的特大暴雨．目的是探寻暴雨中尺度特征与发生机理，并将较高时空密度的非常规观测资料用于综合诊断研究中，以有效构建暴雨发生物理模型的可行性探索．（1）此次暴雨是在独特的南支高空急流与低空急流耦合背景下，由涡旋及其东南象限频繁出现的中尺度对流系统（meso-scaleconve ctivesy stem，MCS）共同导致；（2）不同于常见的影响华南的中纬度涡旋，此次涡旋来自低纬季风槽中，季风涌携带涡度、水汽、能量不断侵入涡旋东南侧并增强这里的西南风，致使此处汇集有利的物理要素并成为MCS频发的关键区，以水平散度项为主的动力因子对涡旋的形成及初期发展具有重要作用，而以潜热为主的热力因子则促使了涡旋向强盛期发展，涡旋发生发展过程中存在正反馈；（3）MCS体内存在西南气流与偏东气流，两支气流辐合并构成西南一东北向的带状对流云团，云团内部具有更细致的非对称流场结构，流场决定MCS呈现非对称的动热力结构特征、并导致强降雨发生于要素极值区；（4）MCS内强劲的β中尺度西南风速核促使不断积聚的对流有效位能（convective available potential energy，CAPE）最终得到释放，对流降雨由此爆发，频繁生成于带状云团东北侧的更小尺度对流单体直接造成了暴雨中心的雨量峰值；（5）综合诊断方法可以在探索暴雨精细结构特征中发挥关键作用．

英文摘要：

The research on heavy rainfall depended greatly on high-resolution data, which could be obtained by using the intensive observation, model simulation, radar detection, and satellite detection. However, it was difficult to discover the fine features of the heavy rainfall system because the limitation of the method of analyzing the big data mentioned above. Therefore, the paper aimed at introducing a new method （synthetical analysis and classifying diagnosis method, SACDM） for effectively analyzing various kinds of data. SACDM possessed a suit of scheme for the data processing and diagnosing. Firstly, the secondary processed data could be obtained by using various key techniques such as numerical simulation technology, numerical calculation technology, radar mosaic technology, and 3D wind field retrieval technology. Secondly, based on the idea of classifying diagnosis, different data were effectively used to analyze the corresponding features on heavy rainfall. Based on various high-resolution data including the intensive observation data from SCHeREX （South China Heavy Rainfall Experiment）, the radar mosaic data, the radar retrieved data, the meso-scale model data, the satellite data, the convectional observation data, the automatic station data, and the NCEP （National Centers for Environmental Prediction） reanalysis data, the paper studied the fine features of the South China extremely heavy rainfall occurred at 5-7 June 2008 by using SACDM, and the following conclusions could be obtained. The unique coupling between the southerly upper level jet and low level jet （LLJ） was favorable for the South China rainfall event. An obvious low-latitude vortex was discovered. Different from most middle-high latitude vortexes, the vortex was greatly influenced by the southwesterly monsoon surges. Dynamical elements played more important roles than thermal elements during the formation period of vortex. During the mature period of vortex, thermal elements played more important roles than dynamical elements. Di