What Day Is The Autumnal Equinox 2024. But are day and night actually equal. The autumnal equinox, or the first day of fall in the northern hemisphere takes place every year on september 22nd or september 23rd.

In 2024, the autumnal (fall) equinox arrives on sunday, september 22, marking the official first day of fall. At a precise moment each september, usually on the 22nd or 23rd, the sun is directly above the equator, marking the autumnal equinox in the northern hemisphere.