When does autumn actually begin?

If you ask a meteorologist, autumn sets in when the average temperature drops below 10 degrees Celsius.

How climate change is affecting the seasons

Fall equinox: Why the first day of fall isn't as equal as you might think

When does autumn start? - Met Office

California Fall Colors: 18 Stunning Places To Visit This Autumn For Foliage

Autumn Equinox - When Does Autumn Begin? - Twinkl NewsRoom

Autumn Equinox - When Does Autumn Begin? - Twinkl NewsRoom

Autumnal Equinox 2023: First Day of Fall, Facts, Folklore & More

No, autumn leaves are not changing color later because of climate change - The Source - Washington University in St. Louis

Autumn - 絵画