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

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
2906:2006:4818:3218:6011 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