摘要
利用贵州国家观测站和区域自动站数据,结合NCEP再分析资料、FY-2G卫星云图及多普勒雷达资料,对2020年6月23~24日在贵州南部地区发生的梅雨锋西段持续特大暴雨过程进行诊断分析。结果表明:(1)此次持续特大暴雨过程是在南亚高压控制、西太平洋副热带高压北界稳定维持在华南北部背景下,短波槽东传及中低层切变和梅雨锋共同影响的结果;(2)来自孟加拉湾的西南暖湿气流与副高西侧的偏南气流在贵州中东部到长江流域一带交汇,促使低空急流建立,为持续性暴雨天气提供充足的水汽输送;(3)高空辐散、中低层切变线南侧与低空急流北侧的正垂直螺旋度为中尺度涡旋迅速发展和水汽辐合抬升凝结提供了动力条件;(4)高原槽引导弱冷空气南下有利于梅雨锋锋生,午后至傍晚生成若干γ、β尺度的中尺度对流系统导致了此次降水过程的发生;(5)暴雨过程中存在明显“列车效应”,贵州南部受对流系统叠加影响形成较强降水。
Based on conventional observation data,automatic station data,NCEP reanalysis data,FY-2G satellite cloud images,and radar data,one continuous heavy rain in the western Meiyu front in Qiannan from 23 to 24 June 2020 was analyzed.Results are as follows:(1)This event occurred under a control of the South Asia High,with the northern boundary of Western Pacific Subtropical High maintaining in the northern South China,the eastward transmission of the shortwave trough and the joint influence of the middle-low shear and Meiyu front.(2)The southwest warm airflow from the Bay of Bengal and the further south airflow from the west of Subtropical High converged in the middle and the east of Guizhou to the Yangtze River.which promoted the establishment of low-level jet flow and provided sufficient water vapor transport for persistent rainstorm weather.(3)The high-altitude divergence,the positive vertical helicity on the south side of the middle-low shear line and the north side of the low-altitude jet provided the dynamic conditions for the rapid development of mesoscale vortex and the condensation of water vapor convergence.(4)The weak cold air southward led by the plateau trough was beneficial to the Meiyu frontogenesist.severalγandβ-scale mesoscale convective systems were generated from afternoon to evening.which caused this precipitation process.(5)There was an obvious“train effect”during the heavy rain.The heavy rain was formed in Southern Guizhou due to the continuous convective system.
作者
张艳梅
顾欣
陈杨
赵杰
莫乙冬
ZHANG Yanmei;GU Xin;CHEN Yang;ZHAO Jie;MO Yidong(Guizhou Meteorological Observatory,Guiyang 550002,China;Qiannan Meteorological Bureau of Guizhou Province,Duyun 558000,China;Guizhou Key Laboratory of Mountainous Climate and Resources,Guiyang 550002,China)
出处
《高原山地气象研究》
2022年第3期58-66,共9页
Plateau and Mountain Meteorology Research
基金
中国气象局预报员专项(CMAYBY2020-117)。
关键词
贵州南部
梅雨锋西段
持续特大暴雨
诊断分析
Southern Guizhou
Western of Meiyu front
Sustained extreme heavy rain
Diagnostic analysis
