2010年8月晋城一次大暴雨天气过程分析

目的]分析2010年8月晋城一次大暴雨天气过程。方法]利用常规气象资料、自动站资料、多普勒雷达资料、卫星云图等资料,从环流背景、物理量场、卫星云图、雷达回波特征等方面,对2010年8月18～19日发生在山西晋城的一次强降雨过程进行综合分析。结果]此次暴雨产生于西低东阻的环流场中,是在中低层切变线、低空急流等有利的天气形势下产生的,低层切变、风向辐合均有利于晋城地区附近不稳定空气的抬升,而对流层低层和地面冷空气的入侵是这次对流天气产生的主要触发机制;西南低空急流为暴雨区输送了充沛的水汽,高温高湿为暴雨的发生积蓄了大量的不稳定能量;这次过程的主要降水系统是地面中尺度切变线扰动激发的对流回波单体,对流回波单体在中低空西南气流的引导下,向晋城移动形成列车效应,在晋城地区产生了大暴雨;多普勒雷达资料揭示了此次中尺度暴雨系统的发生、发展、移动的特征;强降水中心位于TBB低值中心后方的梯度大值区内。结论]该研究为此类短时暴雨的预报、预警提供借鉴。

Analysis of one Heavy Rainstorm in Jincheng in August in 2010

Objective] One heavy rainstorm in Jincheng in August in 2010 was expounded.Method] By dint of the conventional meteorological data,automatic weather station data,and Doppler radar data,and from the aspect of circulation background,physical quantity field,satellite cloud image,and radar echo etc.,one severe torrential rainstorm was analyzed.Result] The rainstorm was in the circulation field of low-west-east-obstruction,and was formed under the middle and low layer shear line and low air torrent situation.The low layer shear and convergence of wind were favorable to the lift of unsteady air around Jincheng.The intrusion of cold air in the low layer of convective layer and above the ground was the main trigger of the generation of such convective weather.The torrent of the low air in the southwest sent abundant water vapor to the rainstorm area.The high temperature and the highly moisture accumulated much unsteady energy for the generation of rainstorm.The main precipitation system of this process was the singular of convective echo which was stimulated by the ground meso-scale shear line.Under the guidance of southwest airstream of the low and middle air,the convective echo singular formed train effect by moving towards Jincheng and formed large rainstorm.Doppler radar data suggested that the characteristics of the generation,development and movement of this meso-scale rainstorm system.The strong precipitation center was in the large value area of the gradient in the back of the TBB low value center.Conclusion] The study provided reference for the forecast and pre-warning of temporary rainstorm of such kind.