Summer officially ends with the Autumnal Equinox that generally occurs between 20-23 September. An equinox, unlike the solstice, is when the sun is almost directly over the equator (the solstice is when the sun is the farthest north or south). Since the Earth is tilted, this allows our planet to receive more or less sunlight during certain times of the year. There are two equinoxes: the Autumnal Equinox in September and the Vernal Equinox in March. The Autumnal Equinox ends summer and begins autumn in the Northern Hemisphere but the opposite in the southern. For them it is the Vernal Equinox beginning spring. For the Northern Hemisphere, the Autumn Equinox for 2026 is 8:04 P.M. EDT. Check timeanddate.com for it to begin in your region.
The transition from summer to autumn begins a period where days begin to get shorter and the nights longer. While summer warmth will linger in some places, much cooler nights are to be expected. Harvests take place during the fall and preparation for storing food for winter also begins. There are many wonderful harvest festivals that take place during this time and since Halloween is not far off, pumpkins begin appearing in large numbers along with haunted hayrides and haunted houses. Oktoberfest, a major event in Germany, starts in September and lasts until early October (with many cities around the world having their own as well).
The full moon nearest the equinox is called the Harvest Moon and in the old days its illumination would help farmers harvest at night for several days. As less daylight occurs, leaves on trees begin changing color resulting in spectacular displays in many places. Some journey far and wide to see the breathtaking images that can occur at this time of year. If you grew up in an area with lots of trees, then another custom was often observed: raking up leaves! Piling them allowed for some creative fun with family members (and pets). Fall foliage comes into full bloom while other plants and trees begin to slow down in preparation for winter. Bird migrations (along with butterflies) begin as they follow the Sun south.

Lilla Frerichs
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Halloween 2026 will not only be the last day of October but also Daylight Savings Time in the United States (and other places it is observed) as clocks are switched back an hour on November 1 at 2 A.M. Usually this occurs on the first Sunday after Halloween but since the first Sunday is the next day in 2026, we set clocks back one hour that night. This will not occur again until 2037.

For More Information
Boeckmann, Catherine. “When Is the First Day of Fall? Autumnal Equinox 2026.” Almanac.Com. Last modified September 18, 2026. Accessed September 21, 2026. https://www.almanac.com/content/first-day-fall-autumnal-equinox.
“Autumnal Equinox | Definition, Dates, & Facts,” Encyclopedia Britannica, last modified July 12, 2025, accessed September 21 2026, https://www.britannica.com/science/autumnal-equinox.
Ashim. “September Equinox 2026: All You Need to Know – Space & Telescope.” Space & Telescope, September 21, 2026. Accessed September 21, 2026. https://spaceandtelescope.com/september-equinox-2026/.
“When Is Fall 2026 & 2027?,” accessed September 21, 2026.
https://www.timeanddate.com/calendar/autumnal-equinox.html.






