Abstract: Selecting a case of severe convective gale disaster in Sichuan Province, the probability distribution function of time, space and intensity of severe convective gale disaster is derived on the basis of the maximum entropy principle by using the average wind speed data of automatic weather station from 2009 to 2019. According to its distribution function, the meteorological parameters that can fully characterize the time, space and intensity of strong convective gale disaster weather process are determined. The grey correlation degree method is used to calculate the correlation degree of meteorological parameters and determine the weight of parameters, taking the direct economic loss of strong convective gale disaster as a reference. The results show that this index can correctly reflect the intensity of disaster-causing ability of strong convective gale disaster process. The larger the index is, the stronger the disaster-causing ability is, and vice versa.