河北省中东部两次降水误报原因分析.pdfVIP

河北省中东部两次降水误报的原因分析 张唯 熊险平 何璇 （河北省沧州市气象台，沧州 061001） 摘要：沧州市气象台对2009 年8 月16 日和18-19 日河北省中东部两次降水过程为暴雨漏报和 空报，为了找到两次误报的原因，重新对高空图、数值预报、探空图和物理量场进行对比诊断 分析，探寻两次降水潜势的差别、降水量级悬殊的根本原因。结果表明：两次降水都是发生在 副高外围暖湿的西北气流中，虽然前者动力条件和水汽条件明显弱于后者，但其大量不稳定能 量的积累和释放导致了暴雨和强对流的发生；虽然后者高低层都有良好的切变线配置，并且水 汽条件充沛，由于前期降水过后热力条件不足，层结稳定，难以产生强降水。只注重环流系统 的配置和水汽条件，忽视探空资料的应用分析是两次预报失误的主要原因。 Abstract: Cangzhou Observatory made false heavy rain predictions on two precipitation processes occurring on August 16 and 18-19, 2009 in the middle and east region of Hebei Province. In order to find reasons for two false forecasts, upper weather charts, numerical forecast, sounding charts and parameter fields were compared, diagnosed and analyzed again to explore the root cause of difference between two precipitation potentialities and disparity in precipitation levels. The results showed that the two precipitations both occurred in warm and wet northwest air stream around subtropical high. Although the former dynamic and vapor conditions were obviously weaker than those of the latter, the accumulation and release of a large amount of unstable energy led to the occurrence of heavy rain and strong convection; Although with good shear line configuration in high and low troposphere and abundant vapor conditions, due to the insufficient thermal conditions and stable stratification after early precipitation it was difficult to generate heavy rainfall for the latter one. Only focusing on the configuration of circulation and vapor conditions, ignoring the application and analysis of radiosonde data were main reasons for the two forecast errors. 关键词：暴雨 误报 潜势 诊断分析 1 引言 夏季降水预报，特别是暴雨预报，一直是专家学者重点研究的对象，因为其强度强、影响 范围广，不确定因素多，暴雨预报的准确率仍不尽人意，如何做好夏季暴雨的预报是一个长远 课题。本文针对河北省中东部夏季两次暴雨预报失误，利用常规气象资料、探空资料和VIPS 雷 达资料、数值预报产品中多物理要素，对两次降水过程的发生潜势进行对比诊断分析，探讨误 报原因，为日后夏季降雨量级和落区预报提供启示和参考。 2009 年8 月16 日夜间河北省中东部沧州、衡水的13 个观测站降暴雨，其中沧州市区降107 毫米（图1a），而根据16 日08 时常规气象资料预报未来24