【摘要】 根据长江三峡地区６个测站１９６１—１９９４年１０月—１月的逐日降水量确定该地区发生区域性强降水的雨日，用同期的历史天气图分析该地区产生区域性强降水的原因、影响系统和环流形势特征，总结归纳出长江三峡地区产生区域性强降水的两脊两槽型大气环流形势的环流特征，概括为一种较为实用的预报长江三峡地区枯水期产生区域性强降水的预报模型，并进行逐日反查，概括出该种环流型产生区域性强降水的前期预报指标。１９９５年的检验和１９９６年１０、１１月试报结果表明，两脊两槽环流型及其相应的前期预报指标是具有预报参考价值的更多还原

【Abstract】 Using the daily date of precipitation of six stations in Sanxia area during October to January from 1961 to 1994,the days of regional severe precipitation in the area are defined.The reasons,the impacting systems and the features of general circulation for regional severe precipitation in the area are analysed by using the historic synoptic charts during the same period.The features of general circulation of two ridges and two troughs model during the regional severe precipitation in Sanxia area are summarized.A synoptic model for forecasting regional severe precipitation in dry season in Sanxia area on the Changjiang is given.The predictive indexes of the circulation pattern is drawn. The operational experiment result shows that the two ridges and two troughs model and its predictive indexes are of referential value to forecast the regional severe precipitation in dry season in Sanxia on the Changjiang.更多还原