用雷达等观测资料以及LAPS(Local Analysis and Prediction System)中尺度再分析场资料,对2009年6月14日在河南、安徽等地引发冰雹大风天气的两个强对流系统的形成演变过程中的对流云合并现象进行观测分析.研究表明,不论是单体间的合并还是对流系统间的合并,合并后单体或对流系统都有显著的增强,并且和强对流天气的发生关系密切.安徽整个对流系统的形成经历了"小单体-大单体或积云团-小的对流系统-大的对流系统"多阶段的合并过程,强对流天气发生和对流系统的阵风锋有关,合并过程中阵风锋达到最强;对流单体的合并和低层气流的相互作用有关,是单体自身的出入流和环境引导风共同作用的结果.LAPS中尺度再分析场资料的结果说明层结不稳定、中尺度辐合和垂直风切变是这次强对流系统形成和对流云合并的重要条件.%Cumulus merging in two severe convective systems occurred in Henna and Anhui on June 14, 2009 was analyzed based on radar data and data of LAPS( Local Analysis and Prediction System).The results showed that both cell merger and convective system merger enhanced obviously and developed into severe convective weather. In Anhui region, the development of the mesoscale convective system included clouds merger from small cell to large cell or cloud cluster, then to small convection system, at last, to large convection system. The severe convective weather was stimulated by gust front , which growed to severest during merging. Both the air flow from the low cells and environmental steering wind played important role in merging process, the interaction between cloud's circulation and environmental steering wind was responsible for cumulus merging. The results of LAPS showed that stratification instability, mesoscale convergence and vertical wind shear were the main conditions for development of cumulus merging and severe convective system.
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