Regardless of the official start date, autumn is defined by several key transitions:
After the autumnal equinox, the Northern Hemisphere begins to tilt away from the Sun. Days become shorter than nights, and the Sun traces a lower, shorter arc across the sky. Temperatures drop as solar radiation decreases, culminating in the winter solstice around December 21. when is autum
The autumnal equinox does not fall on the same calendar date every year. It typically occurs between in the Northern Hemisphere, and between March 20 and March 23 in the Southern Hemisphere. Regardless of the official start date, autumn is
In the Southern Hemisphere, autumn begins on March 20 or March 21 and ends on June 20 or June 21. Regardless of the official start date