【摘要】 2005年10月2日台风龙王登陆福建省,在福州地区引发特大暴雨。卫星云图、多普勒雷达资料和诊断分析表明,台风进入台湾海峡后,其东南侧的西南气流受台湾岛地形影响出现分支而形成的两支气流在福州地区的再次交汇,在有利的环境条件下激发中尺度对流云团发展是这次强降水发生的主要原因。在垂直剖面上θe的非对称鞍形场结构、湿位涡的下负上正分布及高空强辐散和低空强辐合互耦,为大暴雨的发生、发展提供了热力和动力条件。更多还原

【Abstract】 Typhoon“Longwang”, which landed on Fujian Province on October 2, 2005, caused a severe heavy rain over Fuzhou. Based on satellite pictures and Doppler Radar data, diagnostic analysis is conducted. The result indicates that the southwest flow in the southeastern part of typhoon is forced to split into two branches by the impact of Taiwan’s landform after it entered into Taiwan Strait. The two branches of air flow join together again over Fuzhou. Evidences suggest that the developing mesoscale vortex triggered by favorable surrounding conditions is the main reason producing this heavy rainfall. In addition, asymmetry saddle-backed structure of θ_e vertical profile, the upper negative and lower positive moist potential vorticity, as well as the high-level divergence and low-level convergence provide dynamical and thermodynamical conditions for occurrence and development of this heavy rain.更多还原