Fall 2025 Start Date And Seasonal Changes 2025. London the exact moment of the autumnal equinox in 2025 is 22. Autumn 2025 starts on monday, september 22nd in the northern hemisphere, with daylight time shortening and the leaves begining to fall with the changing tilt of the earth's axis.

When will the spring of 2024 start? In 2025, these are the astronomical dates and times for the start of each season: