Start Of Winter 2025. Learn all about the shortest day of the year—and tell us what winter means to you! If the astronomical or calendrical seasons begin with the equinoxes (spring and autumn) and solstices (summer and winter), in meteorology, they begin earlier and correspond to periods of three full months.
Summer begins with the summer solstice, friday, june 20, 2025, 10:42 p.m. Find out the date when winter is in 2025 and count down the days until winter with a countdown timer.