The main characteristics of the general atmospheric circulation in September 2013 are as follows. The polar vortex stretches and splits with its main body located at Western Hemisphere and blocking emerging to the north of Caspian Sea. The Northwest Pacific subtropical high is stronger and more westward extended than normal. The monthly mean precipitation amount is 69.3 mm, which is 6.1% more than normal. There are a series of notable autumn rainfall processes over western China while moderate to severe drought appears in northern Henan with precipitation less than 20% of normal. The monthly mean temperature is 16.8℃, being 0.2℃ higher than normal. There are 2 large range heavy rainfall processes over China, and one of them is related with tropical cyclone. There are 8 tropical cyclones generated in the Northwest Pacific, among which Usagi (1319) is the strongest typhoon that lands at the east coast of Guangdong Province in the recent 40 years. 17 provinces (regions, cities) suffer from severe wind and hail disasters. Central and eastern China is hit by haze.