Vitamin D

The sun, month by month

Sunrise and sunset in Chicago in September

On September 1 in Chicago the sun rises at 06:18 and sets at 19:23; on day 30 it rises at 06:49 and sets at 18:30. Over the month the day gets 83 minutes shorter.

Sunrise06:33
Sunset18:57
Golden hour18:21–18:57
Day length12 h 25 min

Where does the sun rise and set in Chicago in September?

Where it risesEast86°
Where it setsWest274°

Mid-September in Chicago: the sun rises in the east — a bearing of 86°, measured from true north — and sets in the west, at 274°. That is 4° north of due east at sunrise, and the same 4° north of due west at sunset. From the 1st to the last day of the month both points shift 16° south.

Approximate bearings: they can be a couple of degrees out. They are measured from true north, not the north a phone compass points to.

Day by day

All times are local to Chicago. Dawn and dusk mark civil twilight.

DayDawnSunriseSunsetDuskDay length
105:4906:1819:2319:5113 h 05 min
205:5006:1919:2119:4913 h 02 min
305:5106:2019:1919:4712 h 59 min
405:5206:2119:1719:4612 h 56 min
505:5406:2219:1519:4412 h 54 min
605:5506:2319:1419:4212 h 51 min
705:5606:2419:1219:4012 h 48 min
805:5706:2519:1019:3812 h 45 min
905:5806:2619:0819:3612 h 42 min
1005:5906:2719:0719:3512 h 39 min
1106:0006:2819:0519:3312 h 36 min
1206:0106:2919:0319:3112 h 34 min
1306:0206:3019:0119:2912 h 31 min
1406:0406:3218:5919:2712 h 28 min
1506:0506:3318:5719:2512 h 25 min
1606:0606:3418:5619:2412 h 22 min
1706:0706:3518:5419:2212 h 19 min
1806:0806:3618:5219:2012 h 16 min
1906:0906:3718:5019:1812 h 13 min
2006:1006:3818:4819:1612 h 10 min
2106:1106:3918:4719:1412 h 08 min
2206:1206:4018:4519:1312 h 05 min
2306:1306:4118:4319:1112 h 02 min
2406:1506:4218:4119:0911 h 59 min
2506:1606:4318:3919:0711 h 56 min
2606:1706:4418:3819:0511 h 53 min
2706:1806:4618:3619:0411 h 50 min
2806:1906:4718:3419:0211 h 47 min
2906:2006:4818:3219:0011 h 44 min
3006:2106:4918:3018:5811 h 42 min

Approximate astronomical values: they can shift a minute or two from year to year.

What about vitamin D in September?

In September, the typical synthesis window in Chicago runs from 10:00 to 16:00: with medium skin and a t-shirt, ~9 min at the best moment is enough.

See the Chicago vitamin D guide

Common questions about the sun in Chicago in September

Where does the sun set in Chicago in September?
Mid-September in Chicago: the sun sets in the west, a bearing of 274° measured from true north, which is 4° north of due west. It rises in the east, at 86°. Over the month both points shift 16° south.
How much daylight does Chicago lose in September?
Over September the day gets 83 minutes shorter in Chicago: on September 1 the sun rises at 06:18 and sets at 19:23, and on day 30 it rises at 06:49 and sets at 18:30.
How many hours of daylight does Chicago get in September?
In mid-September the day lasts 12 h 25 min in Chicago, from sunrise at 06:33 to sunset at 18:57. The table has the day length for each of the 30 days of the month.
What time does it start to get light in Chicago in September?
In mid-September the sky starts to get light at 06:05 in Chicago, when the sun is 6° below the horizon, and the sun itself does not rise until 06:33. The “Dawn” column of the table gives that time for every day of the month.
What time does it get dark in Chicago in September?
It's not the same time as sunset. In mid-September in Chicago the sun sets at 18:57, but there is still light: civil twilight does not end until 19:25, when the sun reaches 6° below the horizon and usable outdoor light runs out. The “Dusk” column of the table gives that time day by day.
What time of day can you make vitamin D in Chicago in September?
In mid-September, between 10:00 and 16:00: that is the stretch of the day when the UV index reaches 3 in Chicago, the minimum for the skin to make vitamin D. At the best moment of the day about 9 minutes are enough for a mid-range skin phototype with a quarter of the body exposed to make around 1000 IU.