A methodology is proposed for the study of snowfall, applied to the autonomous community of Castilla y León (Spain). It is based on two major pillars: the elaboration of a Snowfall Catalogue from the consultation of documentary sources (press) between 1979-2021, which allows cataloging all the episodes that occurred, from October to May; and the synoptic study of the atmospheric dynamics in those 43 years, identifying the different types of weather as a means of validating the cataloged episodes. The database created provides information on its intensity, duration and frequency, as well as its genesis, distribution, typology and climatic hazard. All this has been analyzed and has allowed to recognize different stages in its way of occurring and to estimate trends and behaviours both in the number of episodes and the number of snow days and their assessment in the current situation of climate change.