2021年广西前汛期一次暴雨过程特征及模式预报偏差分析  

Characteristics of a heavy rainfall process and model forecast deviation analysis in the pre-flood season in Guangxi in 2021

作　　者：梁依玲 刘国忠 赵金彪 刘晓梅 孙红梅 Liang Yiling;Liu Guozhong;Zhao Jinbiao;Liu Xiaomei;Sun Hongmei(Guangxi Meteorological Observatory,Nanning 530022,China)

机构地区：[1]广西壮族自治区气象台,南宁530022

出　　处：《气象研究与应用》2022年第4期104-108,共5页Journal of Meteorological Research and Application

基　　金：广西自然科学基金项目(2022GXNSFAA035482);广西气象科研计划重点项目(桂气科2020Z05);广西气象科研计划重点项目(桂气科2017Z01);广西极端暴雨形成机理及预报技术研究创新团队项目。

摘　　要：利用常规地面和高空观测资料、新一代天气雷达、卫星云图及数值模式等资料,对2021年5月16—20日发生在广西北部、中部的一次较强暴雨过程的特征和预报偏差进行分析。结果表明:(1)本次暴雨过程受500hPa多波动、低层切变线和地面冷空气共同影响造成;(2)地面冷空气移动速度是暴雨强度、雨带位置的重要影响因素。(3)东西向的中空急流(即垂直风切变大)有利于对流云团的加强发展并向东移动形成列车效应,造成东西向强降雨带;暴雨区分布与低层切变线、地面辐合线的走向比较一致;(4)各家数值模式对暴雨落区的预报偏差主要是对地面冷空气、低层切变线以及偏南风急流等天气系统的预报偏差以及模式本身的性能造成的。Using the conventional ground and upper-air observation data,new-generation weather radar,satellite cloud images,and numerical models,this paper analyzed the characteristics and forecast deviations of a strong rainstorm process that occurred in northern and central Guangxi on May 16 to 20,2021.The results showed that the rainstorm process was caused by the combined influence of 500hPa fluctuation,low-level shear line,and ground cold air.The moving speed of the ground cold air entering Guangxi was an important factor in the intensity of rainstorms and the location of the rainband.The east-west middle-level jet(i.e.large vertical wind shear)was conducive to the strenthening and developmet of convetive clouds and move eastward to form a train effect,resulting in the east-west heavy rainfall belt.The distribution of the rainstorm area was relatively consistent with the direction of the low-level shear line and the ground convergence line.The forecast deviations of the rainstorm areas were mainly caused by the forecast deviations of the weather systems such as the cold air on the ground,the low-level shear line,and the southerly jet stream,as well as the performance of the model itself.

关 键 词：前汛期 暴雨 中空急流 预报偏差 

分 类 号：P458.121[天文地球—大气科学及气象学]