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利用济南CINRAD/SA雷达探测资料,结合卫星、自动站和其他常规天气资料,分析了一次弓状回波和强对流风暴的发生、发展,弓状回波和强对流风暴合并形成新弓状回波后又演变成逗点回波的过程。结果表明:(1)强对流过程发生在东北低涡横槽转竖过程,大气环境具有较大的对流有效位能和中等强度的低层垂直风切变。FY-2C卫星的红外云图显示,产生弓状回波的云团是在邻近云团的出流边界影响下发展、加强的,而地面自动站资料清楚地显示出弓状回波影响区域温、压、湿等在20min内发生的剧烈变化。(2)多普勒雷达产品资料分析表明,这是一次典型的弓状回波过程,系统演变经历了典型弓状回波演变过程的每一个阶段:高大对流回波、弓形和矛状阶段及逗点回波阶段。(3)强对流风暴出现在弓状回波前沿约75km的暖区中,具有普通超级单体的一些特征,移动缓慢。(4)弓状回波和强对流风暴合并阶段,弓状回波已处于逗点云系的后期。超级单体逐渐靠近弓状回波的颈部,在短时减弱后又快速发展并填补了弓状回波减弱部分。在弓状回波后侧强入流作用下,超级单体发展成弓状回波,并很快演变成逗点云系,其旋转头部发展很强并产生灾害性大风。“,”Using CINRAD/SA radar data in Jinan,combined with satellite,automatic weather station and other conventional data,the research about occurrenceanddevelopmentof a bow echo and severe convective stormwas studied in this paper.Bow echo and severe convective storms merged to form new bow echo,and it then developed by the process into comma echo.Firstly,Convective process tookplace under the background of horizontaltrough turning to vertical trough.The atmospheric environment existed large convective available potential energy(CAPE)and moderate-intensity low vertical wind shear.FY-2C satellite infrared images clearly showedthat the development andenhancement of bow echowere influenced by outflow boundary of neighbor cloud.At the same time,thetemperature,pressureand humidity observed from automatic weather station had strong changes within 20 min,obviously.Secondly,the result obtained from Doppler radar data indicated that it was a typical bow echo process,because the system evolved through a typical evolution of the bow echo at every stage,such as tall convective echoes,bow and spear-shaped stage,comma echo.Thirdly,the severe convective storm was in the warm area in front of bow echo about 75 km and moved slowly,with some characteristics of common storms.At last,during the stage about bow echo and severe convective storm merging,the bow echo was already in late comma-cloud system.With time going on,the supercell gradually closed to the neck of bow echo.After experienced short decrease,it strengthened rapidly and filled the weakened part of the bow echo.Supercell developed into bow echo withstrong rear inflow in the bow echo,and soon evolved into a comma cloud.The disastrous wind was produced at the rotating head of comma cloud.