The country has 2.4 mm precipitation more than the same period of normal years during January 2010 and the average temperature is 1.4 ℃ higher than that of same period. The cold air is active in this month, but only two of them reach the strong intensity and thus parts of northern Xinjiang suffer from snowstorm . The times of main precipitation process in whole country are up to six in all in this month. Additionally, the polar vortex and subtropical high are stronger than the same period of normal years, but the south branch trough is weaker than the same period of normal years.