【摘要】 用常规天气观测资料、ncep再分析资料、卫星云图、天气雷达等资料对2009年9月16日出现在广东最少雨区之一的罗定市的强降水特大暴雨过程进行分析,结果表明:"巨爵"减弱后的低压系统移动缓慢,其与西伸的"方头"副高之间气压梯度增大,偏南急流在粤西加强和维持是形成"9.16"暴雨的最主要天气系统;边界层内持续的水汽输送和强辐合上升运动是特大暴雨产生的最主要原因;地面弱冷空气的渗透也为暴雨的产生提供了有利的条件;罗定特殊的地形对此次暴雨的形成也十分有利。卫星云图上罗定上空云系稳定少动和雷达回波上南北向的对流云带中的列车效应是这次强降水过程的显著特点。更多还原

【Abstract】 Using conventional weather observations,NCEP reanalysis,satellite imagery and weather radar data,this work studies an exceptionally heavy rain that took place on September 16,2009 in Luoding City,one of the driest areas in Guangdong.The results are shown as follows.The low-pressure system of Typhoon Koppu moved slowly after reduction,increasing the pressure gradient between the subtropical high extending westward and storm itself.A southerly jet stream strengthened and maintained over the western Guangdong,being a main synoptic contributor to the rain.In addition to sustained supply of water vapor and intense convergence and ascending motion within the boundary layer,the main causes for this rain,the intrusion of weak surface cold air and the particular terrain of Luoding are also favorable for the rain.The rain is mainly featured by stationary satellite-captured cloud systems over Luoding and the so-called "train effect" that marked a convective north-south cloud band on the radar echo.更多还原