陕西省10～20天降水预报方法及业务化试验  

Forecast Method and Operational Experiments for 10-20 Days Precipitation in Shaanxi Province

作　　者：杨文峰[1] 刘瑞芳[1] 吴林荣[1] 胡浩[1] 

机构地区：[1]陕西省气象台,西安710014

出　　处：《气象》2009年第12期139-143,共5页Meteorological Monthly

基　　金：陕西省气象局基金课题(2006M-14)资助

摘　　要：介绍了一种制作延伸期降水预报的方法,其步骤是采用欧洲中期天气预报中心(ECMWF)全球模式500hPa高度场格点预报场,与历年同期NCEP再分析资料500hPa高度场进行相关分析,按相关性由大到小排列,取前三个相关系数大的年份。利用历年逐日实况降水资料,得到晴天、小雨、中雨、大雨及暴雨以上5个级别的出现频率,把它当作背景概率,通过背景概率控制获取3个年份中降水场最可能年份,作为最终相似年份,从而获得10～20天的降水预报值。使用该方法进行业务化试验,经检验有较好的预报效果。A forecast method of extended range is introduced.By using the global model of the grid prediction of 500hPa height fields in the European Center for Medium Range Weather Forecasts（ECMWF）,the correlations between the predicted value and NCEP reanalysis data of 500hPa height fields at the same time in the past years are obtained.Among these correlations,three largest correlation coefficients are picked out.Meanwhile,by using daily observed precipitation data in the past years,daily probabilities of sunny,light rain,moderate rain,heavy rain and rainstorm are gained which are treated as background probabilities.The best related year is computed with control of the background probabilities.Taking observed precipitation in that year as the predicted one,so that the prediction for the extended range（10-20 days） will be made.Operational experimentation and verification show that the method is effective.

关 键 词：10~20天 降水预报 相似 背景概率 业务化试验 

分 类 号：P457.6[天文地球—大气科学及气象学] P456.3