宁夏南部山区初夏连阴强降雨过程的物理机制和概念模型

Formation Mechanism and Conceptual Model of the Early Summer Continuous Heavy Rainfall Weather in the Mountain Areas of South Ningxia

选取实况天气场数据、物理量诊断数据和数值预报产品等,采用统计分析、诊断分析和天气学分析方法,分析2012年6月26～29日连阴强降雨天气的形成机制,建立预报概念模型,并分析预报误差原因。结果表明,连阴强降雨过程是环流形势稳定少变、参与系统较多、锋前锋区和锋后均有降水发生的结果;强降雨时虽无不稳定和低空急流,但垂直上升层厚、水汽条件好;欧洲模式的形势和系统相对较好,其他模式的降水预报有优有劣;预报员过度依赖降水预报及对产品性能了解不够是误差的主要原因。

Selecting weather data,physical factors and numerical prediction products,using statistical analysis,diagnosis analysis and synoptic analysis method,the formation mechanism of continuous heavy rainfall during 26-29,June,2012 was analyzed,the prediction conceptual model was established,the causes for error were analyzed.The results indicated that the continuous heavy rainfall happened when the circulation pattern was stable and less variable,the more weather systems participated,and the precipitation occurred before the front,when the front passing and after the front passed.Although no unstable stratification and no low-level jet existed in this heavy rainfall,but the vertical rise layer was deep,and the moisture conditions was well.The circulation pattern and systems of ECWMF was relatively reliable,and there were good and bad in the rainfall forecasting capability of other NWP.The main error reason were attributed to the forecaster＇s over-reliance on the rainfall forecasting of NWP,and the deep understanding capability of the various NWP was not enough.