利用环渤海35个台站1954-2002年近50年逐日平均总云量和低云量的观测资料,统计关注区域内少云、中等云量、多云的发生情况；再用同期NCEP再分析资料,计算出预报关注区域内与不同云量形成相关性较好的各种不同要素的平均场,依据动力过程相似原理,利用T213数值预报产品相邻24 h预报场,以域块距离为依据,建立云量预报模型,制作日平均总云量和低云量4～9天的预报.经过2003-2007年的预报结果与实况资料的对比检验表明:依据动力过程相似方法建立的云量预报模型对日平均总云量和日平均低云量的预报准确率较高；日平均低云量预报准确率要高于日平均总云量;冬半年预报准确率高于夏半年；天空出现少云的预报准确率高于中等云量和多云的情况.%The statistics of cloud cover including low cover, middle cover and high cover were obtained around the Bohai Sea in east China by using historical observational data of daily total cloud cover and low cloud cover at 35 stations from 1954 to 2002. Averrage fields of the meteorological elements related to the three cloud cover formations were calculated with NCEP/NCAR reanalysis data at the same period. Based on dynamic similarity, 4~9 d forecast of total cloud cover and low cloud cover were made on the basis of the domain block distance by using the 24 h adjacent forecast of T213 numerical prediction production. Thus a new scheme was built to forecast the cloud cover. The forecast using the model in 2003 to 2007 was checked by comparing it with the observations and results showed that the annual average forecasting accuracy of the total cloud cover and the low cloud cover have a high standard. The forecast accuracy of the winter-half year is higher than summer-half year. And the forecast accuracy of the little cloud cover is higher than middle cloud cover and large cloud cover.
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