2013年8月16日抚顺特大暴雨过程分析

利用常规观测、加密自动站气象站以及NCEP/NCAR再分析等资料，分析了2013年8月16日抚顺特大暴雨过程。结果表明，抚顺“8.16”特大暴雨过程是一次极端降水过程，具有雨量大、持续时间长、范围广的特点。降水前15天维持高温高湿，低气压特点 。地面蒙古气旋、低层切变线、500hPa西风槽和副热带高压是强降水的主要影响系统。本次降水过程的水汽由多方向气流汇合。低空急流左前方辐合和高空急流右后方辐散耦合，是强降水产生的动力条件。水汽通量散度在降水前为低层辐合，高层辐散。降水开始后辐合中心向下发展，高层辐散明显增大，低层辐合明显加强，对流发展更加旺盛。本次暴雨产生在850hPa假相当位温场高能舌区顶部，垂直分布具有上干下湿不稳定层结。高层干冷空气向低层渗透，触发低层高温高湿不稳定能量释放。地形对降水作用有：1.迎风坡对西南气流抬升作用，2.喇叭口地形汇聚作用，3.浑河河谷狭管作用，4.山地的阻滞作用，5.喇叭口地形再次辐合，五种地形作用叠加而成。

Analysis of the 16 August 2013 Heavy Rainstorm in Fushun,Liaoning Province

Using conventional meteorological observation, automatic encryption station and NCEP/NCAR reanalysis date, analyze the 16 August 2013 rainstorm in Fushun. The results showed that Fushun "8.16" Storm was a process of extreme precipitation, with the characteristics of large rainfall, long duration and wide range. The weather conditions of high humidity and low pressure maintained for 15 days before the process. The Mongolian cyclone, low-shear line, 500 hPa westerly trough and subtropical anticyclone were the major systems which affected the heavy rainfall. The water vapor was gathered by multi-directional airflow. The coupling between the convergence of the low-level jet at the left front and the divergence of the upper-level jet at the right rear provided the dynamic condition. For the water vapor flux divergence, it was convergence in the level and divergence in the upper level before the precipitation. With the start of the precipitation, the convergence center developed to the low level, the upper- level divergence and low- level convergence increased significantly, and the convective motion developed more intensive. The rainstorm was located at the top of the high energy tongue of the 850 hPa height pseudo-equivalent temperature field. The dry at upperlevel and wet at low level vertical distribution was unstable for the atmospheric stratification. The dry cold air at low level transferred to lower, triggering the release of unstable high temperature and humidity energy at low level. Topographic effects on precipitation were as follows: (1) The southwest flow uplift effect on the windward slopes; (2)The bell terrain convergence effect; (3) Hun River valley funneling effect; (4) Mountain blockade effect; (5) The bell terrain preconference effect; (6) Superimposed effects of five kinds of terrain.