Chicago’s Clock Ticking Toward Autumn

Month-long array of daylight milestones

Summer’s long, lazy days may be coming to a close, but not before Chicago experiences a string of milestone moments in daylight.

Milepost number one arrives September 16th, when the city’s daytime hours officially start to shrink. The decrease in daylight is so gradual, however, that it will take nearly two months before we start losing an entire minute of daylight at a time.

Next, the autumnal equinox strikes September 23rd, marking the astronomical start of fall. On the equinox, both the Northern and Southern Hemispheres receive equal amounts of daylight. Day and night will be nearly identical in length all over the planet.

Finally, the month-long daylight countdown concludes October 30th, when clocks “fall back” one hour. This time adjustment brings about the end of Daylight Saving Time and the return to Standard Time. At 2:00 AM on October 30th 2023, the clocks turn back to 1:00 AM.

Losing an hour of sleep in exchange for longer days can be a tough tradeoff. Fortunately, Chicagoans will have plenty of time to prepare. The city will experience small, daily reductions in daylight throughout September and much of October, easing the transition to darker evenings and brighter mornings.