中文摘要：

针对2012年8月30日～9月1日发生在川东北地区的一次暴雨过程，利用24小时加密雨量观测资料、NCEP再分析格点资料，采用Barnes滤波方法及天气学诊断方法，对此次暴雨过程进行了分析。结果表明：在高原槽后冷空气与副热带高压西北侧西南暖湿气流交汇的环境场下，中尺度低压是此次暴雨的直接影响系统；低空西南急流不仅为川东北暴雨提供丰沛的水汽，同时也为中尺度系统的形成、发展提供能量来源和有利的动力条件；大尺度环境场为暴雨提供水汽来源及能量，而中尺度系统在层结不稳定触发下释放潜热产生对流，并为水汽的辐合和向上输送做出贡献；低层辐合、高层辐散的散度配置，有利于暴雨的发生与维持。

英文摘要：

On the basis of the 24-hours precipitation data from the encrypted precipitation station, and NCEP reanalysis data, as well as Barnes band-pass filter, the mesoanalysis of a heavy rainfall happening in northeast Sichuan Basin on August 30 to September 1, 2012 was analyzed. The results show that Under the environmental field of The cold air after Plateau trough and the southwest airflow of warm and moist on the northwest side of the subtropical high, the mesoscale depression was the directly influence system of this heavy rainfall. Low level southwest jet not only provided plentiful vapor for heavy rainfall in northeast Sichuan Basin, but also but also provided favorable dynamic condition and energy source for generation and development of the mesoscale system. Large scale environment field provided water vapor source and energy, and convection happened under stratification instability which made latent heat released as well as made a contribution to water vapor convergence and upward water vapor transfer. The configuration of low level convergence and high level divergence were beneficial to the genesis and maintenance of this heavy rainfall.