It is official...Goodbye, Summer! Hello, Fall! September 22, 2016 marks the Autumnal Equinox!
Equinoxes are opposite on either side of the equator, so the autumnal (fall) equinox in the Northern Hemisphere is the spring (vernal) equinox in the Southern Hemisphere and vice versa.
“Autumn, the year's last, loveliest smile.”William Cullen Bryant