The main characteristics of the general atmospheric circulation are as follows. There was one polar vortex center in the Northern Hemisphere, stronger than usual. The circulation in Eurasian middlehigh latitudes showed a fourwave pattern. The strength of Western Pacific subtropical high was a little weaker than normal. While the south branch trough was a little stronger than normal. The monthly mean temperature was 4.5℃, 0.4℃ higher than normal and the monthly mean precipitation amount was 36.2 mm which is more than normal by 22.7%. Two waves of cold air processes happened in this month, and three regional torrential rain processes occurred during the same period. There were mainly two dust weather events seen in the northern part of China. Besides, severe convection weather appeared in Jiangsu and Hunan.