贵州西部极端对流性暴雨预报失败案例剖析  

Analysis of a Forecast Failure Case of Convective Torrential Rainfall in Western Guizhou Province

作　　者：吴古会 彭芳 张艳梅 WU Guhui;PENG Fang;ZHANG Yanmei(Guizhou Meteorological Observatory,Guiyang 550002,China;Guizhou Institute of Mountainous Environment and Climate,Guiyang 550002,China)

机构地区：[1]贵州省气象台,贵州贵阳550002 [2]贵州省山地环境气候研究所,贵州贵阳550002

出　　处：《中低纬山地气象》2022年第4期17-24,共8页Mid-low Latitude Mountain Meteorology

基　　金：中国气象局暴雨创新团队(CMACXTD002-3);西南区域重大科研业务项目(西南区域2014-3):基于配料的西南区域强降水的中尺度分析;贵州省气象局科研业务项目(黔气科登[2021]10-09号):2020年9月贵州初秋极端持续性暴雨成因分析。

摘　　要：2020年6月1—2日,贵州西部发生了1次局地性的对流性暴雨过程,预报员和各数值模式对此次过程的预报量级显著偏小,对暴雨范围的低估,造成了特大暴雨、大暴雨的漏报。该文利用常规地面、高空资料,加密自动站观测资料,多普勒天气雷达资料,卫星资料及业务中常用的数值预报产品等对此次暴雨漏报案例进行剖析,结果表明:在弱天气尺度强迫背景下,高温高湿的环境中,未能准确判断对流的触发条件,未分析出露点锋、偏西风和偏南风的辐合、冷池和地面辐合线等的存在及其对强降水的影响,加之难以在短时间内对风场的发展演变进行精细分析,导致此次暴雨过程漏报;对于发生在暖湿气团中的对流性降水的预报,需考虑高温高湿环境下露点锋、辐合区、冷池、地面辐合线的相互作用触发对流并使其组织化发展,从而导致局地性、对流性强降水的产生;基于地面加密自动站资料和雷达资料等的短时临近预报可以帮助捕捉中小尺度系统,从而提高对此类暴雨的预报准确率。On June 1-2,2020,a local convective rainstorm occurred in the west of Guizhou.The magnitude of forecast by forecasters and various numerical models was significantly lower,resulting in the underestimation of the rainstorm scope and the underreporting of extremely heavy rain and heavy rain.The cause of the failure forecast of this convective torrential rainfall case is analyzed by using surface and radiosonde observation,encrypted automatic station observation data,Doppler weather radar data,satellite data and numerical forecast products commonly used in business.The results show that failure of capturing the trigger conditions,such as dew-point front,convergence area which consisted of southerly wind and westerly wind,cold pool,surface convergence line,as well as their effects on heavy rainfall under a high temperature and high humidity conditions was one of the important factors leading to the underestimation of the rainfall.Furthermore,insufficient fine analysis on the wind field also caused the failure.Therefore,in terms of forecasting the convective rainfall within a very thick warm wet air mass,the triggering caused by dew-point front,convergence area,cold pool,surface convergence line,organizational development of local and convective precipitation must be considered.Short-time forecast and nowcasting based on surface automatic weather station observation and weather radar data could effectively enhance the ability in finding mesoscale and small-scale systems,which may improve the accuracy of forecasting convective rainfalls.

关 键 词：对流性暴雨 漏报 可预报性 

分 类 号：P458.121.1[天文地球—大气科学及气象学]