EN
The paper concerns characterization of daily course of air temperature in days with spring and autumn frosts depending on kind of air mass. The study was based on the data collected from 2003 to 2010 by automatic station, situated in the west sicie of Bydgoszcz. The paper shows, among other things, terms of appearance and disappearance subzero temperature in days with spring and autumn frosts depending on kind of air mass.