中文摘要：

利用非静力中尺度模式MM5对2008年6月5日北部湾一次引发大暴雨过程的海风锋系统进行模拟研究，结果表明：（1）模式成功模拟出了降水落区、强度及时间变化；此次强降水天气过程是由于海陆风环流引发的中小尺度海风锋系统所造成。（2）日出至午后14时，北部湾沿海区域，伴随着西南强风气流和出海高压后部的东南风气流，来自印度洋海域和南海海域的两股相对高温、高湿空气在与内陆相对较干较冷的空气相遇，来自洋面的两股暖平流叠加，造成温度梯度增大；暖湿气流堆积后，不稳定能量增加，激发了对流运动，引发海风锋生。降水区域大致位于两个不稳定能量轴之间，随着能量轴的移动而移动，同时能量轴在不断深入内陆的过程中不断消耗减弱，降水强度随着减弱。（3）此次海风锋发生、发展和消亡的整个过程集中在日出至14时前后，海陆温度的分布是由暖海冷陆转变成暖陆冷海的过程中。海风锋的整个垂直对流尺度大约在5km，主要的对流发生在950。800hPa层（约0．6～2．0km），水平尺度约40～60km，是一种近地面层的中一卢尺度系统。（4）海风锋自海岸线向内陆的入侵过程中强度逐渐减小。空气流厚度紧靠锋面处较低，其后迅速增大，锋面过后空气流厚度缓慢减小，充分表现出海风锋结构上存在的一个隆起的“头”的特征。

英文摘要：

Using MM5, a mesoscale model, the sea breeze from （SBF） inducing a rainstorm process in Beibu Gulf on 5 June 2008 was simulated. The results show as follows. （1） The model successfully simulated the area, intensity and time of rainfall. The heavy precipitation process was caused by an SBF in a small-scale circulation system under the environmental background field with such synoptic scale systems as a high-altitude ridge, southwest monsoon, and low-level jet. （2） From sunrise to 14： 00, two relatively hot, humid airstreams separately from the Indian Ocean and South China Sea encounter relatively dry inland cold air in the coastal areas of Beibu Gulf. The warm ocean advection superimposed, increasing temperature gradients. With the accumulation of warm air, instable energy increases the stimulated convection, resulting in sea breeze frontogenesis. A precipitation zone is located roughly between two axises of unstable energy. The energy axis weakened continuously while moving inland, the intensity of precipitation diminished. （3） The vertical scale of this SBF is about 5 km, with convection mainly occurring in the 950 - 800 hPa layer, and a horizontal scale of about 40 ~ 60 km, belonging to a mesoscale system in the near-surface layer. （4） The intensity of SBF is decreasing during the process of its movement from coastline to inland. The thickness of the air flow demonstrates a bulge, i.e. the structure of a ＂head＂ feature. In the ＂head＂ part there is a relatively dry zone that is surrounded by nearly saturated moist air and corresponds with the updrafts center.