What Day Is The Fall Equinox 2024 Uk. In 2024, the autumnal (fall) equinox arrives on sunday, september 22, marking the official first day of fall. The first day of fall is sunday, september 22, 2024—the same day as the autumn equinox—in the northern hemisphere.

As with the spring equinox this is a point of seasonal equilibrium with days and nights being almost. But did you know there are actually three main definitions for the season coming from astronomy,.