【作者】 黄先伦； 郭圳勉； 黄小丹； 程正泉；

【Author】 Huang Xianlun;Guo Zhenmian;Huang Xiaodan;Cheng Zhengquan;Yangjiang Meteorological Office of Guangdong Province;Guangdong Central Mereorological Observatory;

【机构】 阳江市气象局； 广州中心气象台；

【摘要】 本文利用NCEP再分析1°×1°资料、广东省雨量资料和探空资料,对"9.21"粤西特大暴雨动力和热力特征进行分析。结果表明,特大暴雨是在台风"凡亚比"和超级低空急流共同作用下产生,并且正涡度平流和暖平流使得当地垂直上升运动增强;超低空急流爆发触发动力抬升,同时输送不稳定能量。强降水发生前,粤西地区有强大气不稳定层结,降水发生时,暖平流随高度减弱以及低层湿平流高层干平流使得大气不稳定性得以保持,而且低层湿平流增加,使得降水长时间维持。强降水发生前阳江站CAPE有明显的剧增,这对暴雨预报有指示意义。更多还原

【Abstract】 The dynamic and thermal characters of "9.21" rainstorm in western Guangdong was analyzed by using NECP/NCAR 1°×1° 6-hourly reanalysis data, rainfall data and radiosonde data of Guangdong Province. It shows that the rainstorm was caused by the combination of typhoon "Fanapi" and super-low-level jet. The vertical movement was strengthened caused by the positive vorticity advection and warm advection. The outbreak of super-low-level jet triggered the lifting of dynamic and transported the unstable energy. Before the starting of rainstorm, unstable atmospheric stratification was strongly in Western Guangdong; while raining, warm advection decreased with height, and the atmospheric instability was kept by the low wet advection and high dry advection. Furthermore, the increasing of low wet advection lead to the long time maintain of rainfall. Before the occurrence of heavy rainfall, the CAPE of Yangjiang station increased surgely, which was indicative significance for the forecasting of rainstorm.更多还原