[Objective] The aim was to study the sea breeze front storm and its composite analysis in Beibu Gulf. [ Method] By dint of routine observation data, ground automatic meteorology data and European numerical mode grid data, rainstorm caused by Guangxi sea breeze during 1990 and 2007 and the strong convection triggered by sea breeze on June 5 in 2008 were expounded. The main characteristics of the configuration of circulation in the low and high latitude of breeze front of middle scale were summarized. [ Result] Sea breeze front storm system was an important middle scale sea breeze front system that triggered storm in the Beibu Gulf. Sea breeze in Beibu Gulf occurred most easily during the southwest monsoon eruption period. Case study pointed out that after sunrise, the continental and island temperature in Beibu Gulf turned from warm-ocean-cold-island into warm-island-cold-ocean. The southerly airstream of high temperature and high humidity met with the relatively low temperature and dry northerly airstream in Beibu Gulf, and triggered vertical circulation and stimulated ground middle scale sea breeze front system. Composite analysis referred to the circulation characteristics of the ocean and continental temperature in Beibu Gulf. Tke upper air of south China was in strong divergence center. The air pressure was high in the east and low in the west. Beibu Gulf was in the southerly torrent belt in front of the trough and after the latitude in cyclonic circulation convergence area. The strata unstable structure of the divergence in the upper air and the convergence in the lower layer and the " pumping effect" provided upward dynamics for the ocean circulation development. The southerly brought rich water vapor to the Beibu Gulf, which was conductive to the formation of strong convective cloud system in the lower layer and the generation of precipitation. [ Conclusion] The study provided reference for the study of the characteristics of middle scale convective system.%[目的] 研究北部湾海风锋暴雨过程及合成.[方法] 利用常规观测数据、地面自动气象资料及欧洲数值模式格点数据,对1990～2007年期间广西海风锋引起的暴雨天气过程并结合2008年6月5日海风锋触发的强对流天气个例进行统计和合成分析,归纳出北部湾中尺度海风锋系统高低空环流配置的主要特征.[结果] 海风锋系统是触发北部湾暴雨的一个重要中尺度系统；在西南季风爆发期间最易激发北部湾海风锋锋生.个例分析初步指出日出后,北部湾海陆温度逐渐由暖海冷陆转变成暖陆冷海,高温高温的偏南气流与相对低温干燥的偏北气流在北部湾海区交汇,引发垂直环流并激发近地面层的中尺度海风锋系统.合成分析指出了北部湾海风锋锋生的环流特征,即华南上空高层处于强辐散中心,越往低层气压场呈东高西低的形势,北部湾海域位于槽前高后的偏南风急流带,呈气旋性环流的辐合区;高空辐散低层辐合的层结不稳定结构和“抽气效应”为海风环流发展所必须的上升动力,偏南风为北部湾区域带来了丰富的水汽,有利于低层强对流云系的形成和降水的发生.[结论] 该研究为中尺度对流系统活动的特征分析提供参考依据.
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