What Day Does Winter Start 2025. Winter solstice 2025 (beginning of astronomical winter) on the day of the winter (december) solstice, the sun passes through the southernmost point of the ecliptic, that is, as far as. Winter will last until the vernal equinox on thursday, march 20, 2025.

When in 2025 is winter? To find out why the seasons occur, visit this page: