Fall Equinox 2024 Dates. In 2024, the autumnal (fall) equinox arrives on sunday, september 22, marking the official first day of fall. Autumn equinox 2024 (beginning of astronomical autumn) on the day of the autumn (september) equinox, the sun, moving along the ecliptic, crosses the celestial equator,.
When is the 2024 autumn equinox? Cdt) on september 22, 2024.