What Day Is The First Day Of Winter 2024. But what exactly does this mean, and why does the winter solstice begin on this day? The first day of astronomical winter is saturday, dec.
Fall begins with the autumnal equinox, sunday, september 22, 2024, 8:44 a.m. 22 (only a few days before christmas) in the northern hemisphere, and on june 20 or june 21 in the southern hemisphere.