利用常规气象观测资料、NCEP 1.0°×1.0°再分析资料、欧洲高分辨率(0.75°×0.75°)再分析资料以及区域自动站资料和多普勒天气雷达资料，采用天气学诊断分析方法，对2013年第11号超强台风“尤特”(1311号)残留低涡在广西和湖南一带的复杂移动路径及其长时间维持与复苏造成广西特大暴雨的成因进行分析。结果表明：(1)大陆高压、西太平洋副热带高压与赤道高压形成合围态势，热带辐合带北抬加强，是造成“尤特”残留低涡在华南西部缓慢移动、运动路径先北移后南落的环流背景；(2)弱的垂直风切变环境，季风急流与“尤特”残留低涡长时间联结，有利于水汽和不稳定能量补充到“尤特”残留低涡中，是造成其长时间维持的原因；(3)“尤特”残留低涡后期向南移动过程中，与季风急流(季风涌)相遇获得潜热能，是造成残留低涡复苏并促使降水增幅的原因；(4)分析雷达回波可知，在“尤特”残留低涡东南侧，风暴单体呈螺旋带状并形成列车效应。%Based on conventional meteorological observation data, NCEP 1° × 1° reanalysis data, reanalysis data with resolution 0.75° × 0.75° from ECMWF as well as observations from automatic weather stations and Doppler weather radar, we analyze the cause of a torrential rain in Guangxi induced by residual vortex from super severe typhoon Utor (1311) by dynamic and thermodynamic diagnosis. The results show that (1) the encirclement situation formed by continental high, subtropical high over the west Pacific and equatorial high and, the reinforce-ment and northward movement of the tropical convergence zone, resulted in the residual vortex from Utor moving slowly in the western South China first northward and then southward. (2) Weak vertical wind shear and the long duration of connection between monsoon surge and the residual vortex are favorable to moisture and unstable energy supplementing to the Utor residual vortex, which lead to a long continuance of the vortex. (3) When the residual vortex moved southward at the later stage, it encountered with monsoon surge to obtain latent heat, which is the main reason of the vortex resuscitated and precipitation increased. (4) Analysis of radar data showed that at the southeast of the residual vortex the storm cells formed a shape of helical ribbon and caused the train effect.
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