Fall in Chicago may have unofficially begun after Labor Day, but the scientific first day of the season doesn’t arrive for another week.
The autumn equinox in the Windy City brings the return of the Chicagohenge phenomenon, the Harvest Moon, and other notable changes to our environment.
Here’s everything to know about the equinox in Chicago.
When does the fall equinox occur?
The fall equinox in the Northern Hemisphere will occur on Tuesday, September 22, at 7:05 p.m. according to Time and Date.
The equinox marks the moment the sun crosses the celestial equator. After this point, the Northern Hemisphere enters astronomical fall.
When is the Chicagohenge phenomenon?
Both the spring and fall equinoxes in Chicago coincide with the Chicagohenge phenomenon, a period wherein the rising and setting sun aligns perfectly with the city’s grid pattern.
During Chicagohenge, city dwellers can head downtown to watch as the sunset and sunrise illuminate the Chicago streets from east to west in spectacular fashion.
The Chicagohenge dates for 2026 are between September 19 and 22 according to the Adler Planetarium.
Does the fall equinox coincide with the Harvest Moon?
This year the Harvest Moon in Chicago will follow just a few days after the fall equinox, occurring on Saturday, September 26.
The moon will begin its rise at 6:29 p.m. Arguably the best time to view the Harvest Moon is during the first few hours of its ascent, as the moon will appear in a red or orange hue.
