November
Autumn.
The Australian autumn begins March 1st and ends May 31st
equinox
Start from september
Autumn starts on Sept. 23.
Autumn
Autumn or Fall.
Every place on earth experiences autumn -- and depending on which hemisphere hosts the spot, autumn begins in either in either September (North) or March (South).
Autumn officially begins on September 21 and ends on December 21 - 3 months.
The first day of Autumn, or the Autumnal Equinox
The answer to this depends on which definition of autumn is being used. In the northern hemisphere, the astronomical autumn begins September 23 at the time of the autumnal equinox. This date is sanctioned by the International Astronomical Union and can vary by a day or two from one year to the next. The climatological autumn begins September 1. This date is sanctioned by the World Meteorological Organization for the northern hemisphere and never changes. The ecological autumn begins locally whenever the leaves change colour and start to fall. This date varies from one region to another and can shift from one year to the next.
Summer is June to August. It begins after spring ends, May, and ends when autumn begins, September. Hope this helped.