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利用济南和滨州两部新一代多普勒雷达反演的三维风场,分析了发展成熟和减弱阶段的弓状回波、强对流风暴的三维风场结构,以及两者合并过程的风场变化特征。结果表明：（1）弓状回波的头部和尾部分别对应气旋性和反气旋性环流,气旋性环流较强。在逗点云系阶段,回波强度、主上升气流,以及气旋和反气旋性环流开始减弱。（2）强对流风暴靠近处于消散期的旧对流风暴时产生了较强的下沉气流,促使强对流风暴的产生和发展。强对流风暴的强回波区在低层为风场辐合中心,而高层则对应辐散流场。（3）强对流风暴和弓状回波合并过程显示,弓状回波处于逗点云系阶段的后期,前沿只有弱的上升气流,而强对流风暴处于成熟、减弱阶段,靠近弓状回波一侧有较强的下沉气流,两者相互靠近的过程中弓状回波前沿的弱上升气流与较强的下沉气流汇合,导致弓状回波迅速减弱,强对流风暴也短时减弱。随着弓状回波后部有组织的后侧入流的侵入,强对流风暴中的暖湿气流被剧烈抬升,促使风暴发展的更加强盛。“,”Three-dimensional wind field structure of a bow echo and a severe convective storm and interaction between them were studied in this paper,using the dual-Doppler（located at Jinan and Binzhou） retrieved wind field.The variations of wind field during the stage of the bow echo and severe convective storm merging were also analyzed.The main results were as follows： Firstly,the cyclonic circulation and anticyclonic circulation located at the head and tail of bow echo,respectively.But the cyclonic circulation was stronger than anti-cyclonic circulation.In the comma stage of cloud,the echo intensity and main updraft weakened,but the cyclonic and anti-cyclonic circulation strengthened.Secondly,the strong sinking divergent flow generated from old convective storm in the stage of dissipation,promoted convective storm formation and development.In the strong echo zone of severe storm,the convergence center located at the lower level,corresponding divergent field at the upper level.Finally,during the stage between severe storm and bow echo,the bow in the later stage of comma cloud,had weak updraft at the front of itself.But at the same time,the severe storm was in the mature stage,with strong downdraft close to the side of the bow echo.When the severe storm and bow echo closed,weak updraft and strong downdraft airflow merged.This situation led to rapid weakening of bow echo and short-time weakening of severe storm.As the organized rear inflow invaded back in the bow,the warm and wet airflow in severe storm was uplift.So the storm was encouraged an developed more powerful.