Abstract: July 9,2012,a strong precipitation in xiaoergou region,64.8mm 6 hour precipitation,reaching large ～storm.The precipitation is in the run-up to the formation of the Northeast cold Vortex process,West of the trough,low level shear and surface cyclones moving eastward combined effects caused by local heavy rainfall.This use of weather charts,physical quantities, radar,single station meteorological elements on an integrated analysis of the process.