Using the data of precipitation and NCEP in Anhui, two continues severe snow processes in 1969 and 2008 are studied, with emphases on the change of the blocking high in the Ural Mountain and the southwest wind over the south of Anhui at 700 hPa. It is found out that before both sever snow processes, the blocking high in the Ural Mountain was strong, and the two snow processes began from the weakening of the blocking high; about 1 or 2 days before or after the index of the blocking high dropping to the lowest, the southwest wind being strong at the same time, the snow enhanced obviously. The quasibiweekly oscillation of the moisture transport in the south of Anhui at 700h Pa was obvious in January and February in the two years. The water vapor origin of precipitation was from the South China Sea in 1969, and from the Bay of Bengal and the South China Sea in 2008