When Is The First Day Of Fall 2025 Usa. The first day of autumn often called fall (september equinox or autumnal equinox) is when the. On the flip side, 2025's winter solstice —.

The autumnal equinox, or the first day of fall in the northern hemisphere takes place every year on september 22nd or september 23rd. On the day of the autumn (september) equinox, the sun, moving along the ecliptic, crosses the celestial.