提为加深对杭州湾影响下飑线维持机制的理解，利用多普勒天气雷达、常规和加密观测资料以及NCEP GFS资料，分析了2014年7月27日浙北飑线成因，并重点探讨了此次飑线过程中对流从北岸和南岸移入杭州湾的演变过程及对飑线整体发展的作用。分析表明：南北向辐合线触发新的雷暴单体生成及中等强度的深层垂直风切变，是此次飑线生成和发展的关键环境条件；飑线中对流从南北两岸移入杭州湾后强度均加强，使得飑线得到更好的维持发展；杭州湾上更好的水汽和更强不稳定能量条件，使从北岸移入杭州湾的对流单体加强并连接苏南、浙北两条线状对流，这是进而使得飑线持续发展的重要原因；杭州湾表面与陆地相当的温度和湿度，以及海上较强的垂直风切变，使南岸入海对流强度维持，并在地面冷池和后侧入流的共同影响下发展成弓形回波，这也是飑线维持的重要因素。%Anstract:To enhance the understanding of the squall line maintaining mechanism under influence of Hang-zhou Bay,the diagnosic analyses are made on the squall line in northern Zhejiang on 27 July 2014,using Doppler radar data,convectional and densely-observed surface data and NECP GFS data.The focus is on the evolution of convection that moved into Hangzhou Bay from the north and the south coasts and its effect on the overall development of squall lines.The result indicates that the north-south convergence lines and moderate strength of deep vertical wind shear are the key environmental factors of the generation and development of the squall line event.Convections are strengthened after moving into Hangzhou Bay from the north and the south coasts,leading to squall line maintaining.The better moisture conditions and unstable energy conditions in Hangzhou Bay result in the further strengthening of convection from the north shore of Hangzhou Bay,and the connection of two linear convections in southern Jiangsu,northern Zhejiang as well as the sustainable development of the squall line.The temperature and humidity on the surface of Hangzhou Bay is equal to the surface of south coast,and the strong wind shear in Hangzhou Bay leads to the maintaining strength of the convection into Hangzhou Bay from the south coast.Under the in-teraction of cold pool and rear inflow,bow echo develops on the sea,becoming an important factor for the maintenance of the squall line.
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