howmuchsun

Vitamin D from sunlight in Uzbekistan

How long you need in the sun to make vitamin D, and when the sun is too low to make any at all, for 4 cities in Uzbekistan.

CityLatitudeElevationVitamin D winter
Tashkent 41.26°N 424 m 4 Nov – 14 Feb (103 days)
Andijon 40.78°N 497 m 6 Nov – 12 Feb (99 days)
Namangan 41.00°N 442 m 5 Nov – 13 Feb (101 days)
Samarkand 39.65°N 703 m 11 Nov – 7 Feb (89 days)

How these dates are calculated