中文摘要：

利用雷达、卫星、闪电定位仪及NCEP资料分析了2007年7月8日在安徽沿淮西部出现的特大暴雨过程的中尺度特征。分析结果表明：造成特大暴雨的强对流回波带与近地面层925hPa辐合区位置一致,而且回波单体移向与回波带走向一致,另外发现该中尺度对流雨团（rainstorms）属于后向传播,其传播方向和单体的移动方向相反,使得强回波在特定区域保持相对静止,造成特大暴雨;逐时降水极值基本出现在对流发展旺盛和对流回波发生合并时。另外通过分析单多普勒雷达反演二维风场发现,中低层气旋性切变的维持是强降水形成和维持的重要条件。

英文摘要：

By using the data of radar and satellite,lightning positioning and NCEP data,the mesoscale characteristics of the excessive storm occurring in the western region along Huaihe in Anhui on July 8th,2007 were analyzed.The results show that the big convective echo band producing the excessive storm was consistent with the convergence area at 925hPa.The convective cell moved in the same direction as echo band,but the mesoscale rainstorms propagated backwards.It moved in the oppositional direction with the single cell which made the big echo relatively stable in a specific area and caused the excessive storm.The maximum hourly precipitation almost appeared when intense convection and convective echo merging.Furthermore by analyzing the two-dimensional wind field retrieved of single Doppler radar,the cyclonic shear maintaining at low and middle level was the important condition which caused and maintained the severe rainfall.