内蒙古“6月25-28日”暴雨天气成因分析

Analysis of rainstorm event over Inner Mongolia during 25-28 June 2012

利用常规观测资料对2012年6月25-28日内蒙古地区暴雨过程进行了分析。结果表明:贝加尔湖高空冷涡发展成熟的有利大尺度环流背景,低层冷暖切变线和地面倒槽是造成暴雨的主要系统,单站暴雨受大尺度系统影响外,不稳定能量的强烈释放和中小尺度系统的发展是主要原因。水汽辐合中心与强降水落区有较好的对应关系,但是个别单站暴雨落区亦有一定偏差。此过程从对流性暴雨开始,随着冷涡后部冷空气的侵入和低空急流的建立暴雨影响区域扩展到我区中东部地区,暴雨的量级增大,持续时间延长。

Synoptic causes of the rainstorm event during 25-28,June,2012 in Inner Mongolia were analyzed by using conventional observation data.The results show that the favorable circulation background made by the mature cold Baikal low,low level cold and warm shear line,ground inverse trough were the main system of torrential rain;Single-point rainstorm was influenced by large scale system,where as the strong release of the strong unstable energy during early period of rainstorm and the meso-micro scale system were the main reasons.Water vapor convergence center and rainfall area had a good corresponding relation,but individual single rainstorm area also had a certain deviation.The process originated from convective torrential rain and followed by the invation of cold air from the rear of vortex and low level jet establishment the rainstorm impact area extended to the area of middle-east region of Inner Mongolia accompanied by increasing rainfall strength and extended duration.