A number of conventional physical variables and convective parameters are computed with mesoscale numerical weather model AREM (Advanced Regional ηcoordinate). The methods for diagnosing severe storm potential are studied accordingly in combination with the fuzzy logic method. Potential forecast products for the location of hailfall, disastrous gust and thunderstorm are developed. The results show that the method can diagnosis well the type and location of severe convective weather, and is of important value for nowcasting in evaluating severe weather potential.