2003年淮河流域致洪暴雨的环流演变

SYNOPTIC PATTERN DURING HEAVY RAIN OVER HUAIHE VALLEY IN 2003 AND RELATED MEDIUM-RANGE FORECAST

使用EC模式的格点高度场和风场资料，分析2003年6～7月欧亚地区环流形势演变特征与安徽淮河流域致洪暴雨的关系发现：淮河流域的强降雨能持续14d之久，是500hPa高空超长波维持2波、长波交替出现5～6波、高纬度为阻塞环流形势以及副热带高压脊长时间稳定在23～27°N偏北位置诸因子共同作用的结果。

Based on geopotential height and wind field grid data from EC model, the relationship between the synoptic pattern over Europe-Asia area from Jun. to Jul. in 2003 and medium range forecast for torrential rain, which caused flood over Huaihe Valley,is analyzed. The results show that the heavy rain over Huaihe Valley that lasted for 14 days was caused by the interaction of the following factors： two waves maintained as extra-long wave over high level of 500 hPa,five or six waves appeared as long wave alternatively, blocking high established in the high latitude and the ridge of the West Pacific subtropical high stably located between 23-27°N that was north to its normal place.