The following are the main characteristics of the general circulation of atmosphere in March 2012. There are multi polar vortex centers in the Northern Hemisphere with slightly stronger strength than normal years. The circulation presents a four wave pattern in middle high latitudes. The south branch trough is slightly stronger than normal years and the situation is favorable for the transportation of water vapor. The strength of the Western Pacific subtropical high is weaker than normal years. The monthly mean temperature is 3.5℃， which is lower than the same period of normal years. The mean precipitation (31.4 mm) is 8.7% more than normal. There are 3 cold surge processes affecting China in this month, the first sand and dust weather process appeared in northern China, and the continuous low temperature and rainy weather occurred in southern China for a long time.