Abstract: Combined the computer pattern recognition and the numerical weather model products, the method of pattern recognition to predict the medium-range weather processes and the process of the pattern primitive element recognition are introduced. With the NWP products of ECMWF, the concept model of medium-range forecast of snow disasters in the northwestern plateau in Sichuan Province is established. The computer imitates the thinking process of forecasters, automatically classifies and judges the different categories to determine whether a snow disaster will occur in the future 3—5 days and which day it will occur. The results of the medium-range forecast of snow disasters are rather good.