一次暴雨天气的诊断分析与预警

Weather diagnosis and early warning of a rainstorm event

2007年9月29日08时至30日08时,长治市出现了历史上罕见的暴雨和大暴雨天气,部分县、市遭受重灾。针对暴雨的成因,从500hPa天气环流背景、700hPa急流影响系统和物理量场的主要参量(相对湿度场、K指数场、散度场)以及FY—2C红外卫星云图的中尺度对流辐合体的演变,进行了综合诊断分析,给出了暴雨预报着眼点。暴雨前及时发布了蓝色预警信号和暴雨地质灾害重要天气警报,为防汛工作的及早安排部署提供了准确的重大决策气象服务。

A heavy rain and rainstorm,which was rare in history ,fell from eight o＇ clock on the 29th through eight o＇clock on the 30th, september , 2007 in Changzhi City. Some countys and citys suffered badly. In view of the cause of the storm, a comprehensive diagnostic analysis of the 500hPa circulation background, 700hPa rapids influence system ,the main parameters of physical field（ relative humidity field ,K index field, divergence field ）and the evolution of the mesoscale convection convergence （MCC）in the FY-2C infrared satellite cloud picture was made, and the focus of rainstorm forecast was given. The issued blue early warning signal and geological disasters of the rainstorm timely and accurately provided weather services for major policy decisions of flood prevention arrangements as early as possible.