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

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.