针对1981-2013年在江淮地区发生的24次持续性异常降水过程,使用江淮地区388个观测站逐日降水观测资料和NCEP/NCAR逐日的再分析资料,采用统计和合成方法,得出33 a江淮区域发生异常降水事件前后的天气学特征.结果表明:江淮流域33 a异常降水过程平均可维持4 d或5d,异常降水初日降水量可达33.02 mm.异常降水过程前后,逐日降水量有一个非常显著的增长且与环流的异常调整有紧密的关系.西太副高的纬向移动现象比较明显,584线维持在江淮地区.江淮地区处于温暖潮湿的偏西风及来自印度洋的热带季风气流两者的共同控制中,受到从印度洋传输来的暖湿西南气流的影响面积逐渐增大,给予充足的水汽和能量,南北经向风在江淮流域上空出现交汇.南亚高压继续向东发展到130°E以东、1252dagpm等值线向北发生位移及200 hPa散度场江淮流域上空辐散中心的加强均对异常降水过程具有预警提示意义.%Based on 24 continuous abnormal precipitation process happened in jianghuai during daily observed precipitation data of the 388 stations and NCEP/NCAR daily reanalysis data,with the methods of statistic and synthetic analysis,the sustainability the synoptic characteristics during the rain period.The results show that the persistent abnormal precipitation can maintain 4 d or 5 d,and the accumulative rainfall reached 33.02 mm at the beginning of the anomalous precipitation.The daily rainfall has a very significant growth after the abnormal precipitation process tak place and have close relationship with the exception of circulation adjustment.The latitudinal translation of western Pacific subtropical high obviously,584 dagpm maintains at jianghuai.ianghuai is under the control of warm and humid westerly and tropical monsoon airflow from the Indian Oceanhe influence of transmission from the Indian Ocean to the southwest increases gradually,giv sufficient moisture and energy,the meridional wind intersects over jianghuai.South Asia high moves to the east of 130 °E,1252 dagpm contour moves to the north,as well as the strengthen of 200 hPa divergence center over jianghuai have prompt early warning for continuous abnormal precipitation process.
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