First Day Of Autumn 2024 Date Uk. The autumn equinox officially marks the end of the summer in the northern hemisphere as planet earth welcomes the fall but when will this actually take place in 2024. An equinox is one of two days in the year when the sun crosses the equator and day and night become equal in length.

The autumnal equinox, or the first day of fall in the northern hemisphere takes place every year on september 22nd or september 23rd. For ease, the meteorological autumn officially begins on the 1st of september 2024.