摘要
利用NCEP资料、LAPS产品、地面自动站资料及卫星资料和多普勒雷达拼图资料,对2009年6月28—30日湖北区域性大暴雨过程的环流背景与动力、热力、水汽条件等进行了诊断分析。结果表明:此次过程是在贝加尔湖低槽东移、副热带高压加强西伸北抬、西南急流发展、低层切变线南压和低涡东移的条件下发生的;低空急流的发展使大气强烈转暖,低层辐合与正涡度、高层辐散与负涡度及其相互配合,为暴雨发生发展提供了有利的热力和动力条件;冷空气南下在高温高湿的长江流域形成锋区以及西南急流加强,不仅向暴雨区提供了充沛水汽,还与切变加强、低涡东移共同造成能量锋区锋生,沿低层θse能量锋区及切变线有多个对流云团和强回波生成引发区域性强降水。
Based on NCEP data,LAPS products,rainfall records from automatic precipitation station,the FY-2C satellite data and Doppler radar data,Hubei Regional Downpour during June 28—30,2009 is analyzed with its circulation background and dynamic,thermodynamic,water vapor conditions and so on.The results show that the event takes place in the background of Baikal Lake trough moving eastward,the subtropical high strengthening in westward and northward advance,the southwest jet developing,the low level shear-line moving southward and the vortex moving eastward.The development of low-level jet makes atmosphere warming strongly and the inter-matching of low-level convergence with positive vorticity and high-level divergence with negative vorticity provide favorable thermodynamic and dynamic conditions for the growth of downpour.Cold air moves southward forming frontal zone in Yangtze River basin and southwest jet is strengthened,all these are not only providing enough vapor to the heavy rain area but also leading to the energy frontal zone frontogenesis with the strengthened shear-line and vortex which moves eastward together.Multiple convective cloud cluster and strong echo created along low-level θse energy frontal zone and shear-line cause the regional heavy rainfall.
出处
《暴雨灾害》
2009年第3期215-221,共7页
Torrential Rain and Disasters
关键词
区域性暴雨
切变线
低涡
低空急流
能量锋生
Regional rainstorm
Shear-line
Vortex
Low-level jet
Energy frontogenesis
