提本文利用常规探测资料、多普勒天气雷达资料、自动站观测资料等对2013年3月27—28日发生在广西的一次飑线大风天气过程进行跟踪及监测预警，对其大尺度环流背景、雷达回波特征以及灾害性大风形成原因进行了较为详细的分析与研究。结果表明：此次飑线过程是由高空冷槽与地面高压后部形势所引起的；假相当位温、T-logp图等分析表明广西上空具有较好的热力、动力条件；地面辐合线触发初始对流活动；发展成熟的飑线地面气压场上存在雷暴高压、飑前低压和飑后低压等中尺度特征；飑线大风等灾害性天气出现在地面高压前侧气压梯度大值区和飑线的断裂处；雷达图像上中层径向辐合、反射率因子核心和中层风速大值区逐渐降低以及垂直风廓线图中低层风的转变等特征信息对地面大风天气临近预警有较好的指示意义；降水粒子的拖曳作用和飑线的快速移动都对地面大风的产生及增幅有一定的作用。%A squall line storm that stroke Guangxi severely in 27-28 March 2013 was traced and alerted based on various observation data collected by conventional meteorological radar,and automatic meteoro-logical stations,etc.This paper particularly analyzes the large scale circulation weather background,the characteristics of radar echo and formation mechanism of gale.The results show that this squall line is caused by the cold trough of high altitude and high pressure of ground.The good thermal and dynamic conditions over Guangxi are demonstrated on graphs of equivalent potential temperature and T-logp.Initial convection is triggered by the ground convergence line.Surface pressure field of matured squall line has the mesoscale features including thunderstorm high,depression before and after the squall.Disastrous weath-ers such as gale of squall usually appear in the area of big values of barometric gradient and the split part of squall line before ground high pressure.On the other hand,the information of radar,including midaltitude radial convergence (MARC),reflectivity core and middle-level greatest speed gradually decrease and the transition of the low-level wind show vertical wind profile chart,which could be well in indicating ground wind.Drag effect of precipitation particles and the fast moving squall line have certain effect on generation and growth of ground gale.
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