2009年7月初广西致洪暴雨过程综合分析

Synthetic Analysis of a Heavy Flooding Rainstorm Event over Guangxi in July 2009

利用常规观测资料、自动站资料、卫星资料和NCEP再分析资料对2009年7月1～6日广西致洪暴雨过程进行分析,发现:850hPa西南急流为广西输送大量的水汽和不稳定能量,急流轴随时间逆转阻断水汽和不稳定能量北上,使之在广西积聚,500hPa低槽下高原后加深并出现闭合低涡,低涡附近强烈的上升运动,触发了暴雨的发生,同时地面闭合低压环流使低层辐合明显,闭合低压环流附近出现强降雨带。桂北静止锋云团、桂南辐合抬升不断加强生成对流云团,是造成了南北两条强雨带的重要原因。

Using conventional observational data, data, the heavy flooding the southwest jet stream automatic station data, satellite data and NCEP reanalysis rainstorm event over Guangxi in early July 2009 was on 850hPa level transports a large number of water analyzed. The results show that vapor and instability energy to Guangxi. The water vapor and volatile energy were blocked northward by the reversal of the jet stream axis and accumulated over Guangxi.The deepening of the high trough, the emergence of a closed vortex and the strong upward motion near the vortex triggered the heavy rain along the ground low pressure circulation.The stationary front clouds in the north of Guangxi and the convective clouds in the south of Guangxi are the main causes of the north and south strong rain belt.