Due to its high altitude, climate of Lhasa feature rarefied air, low oxygen content, poor moisture, which can result in altitude reaction easily for newcomers. Besides, Lhasa has abundant sunshine and strong sun radiation. Known as Sun City, Lhasa enjoys 3,000 hours of sunlight annually. Located in the north of Himalaya, it is influenced by downdraft flow and has a semi-arid climate. Temperature has no big difference during a year but varies dramatically in a day.
June is the hottest season with average temperature being 15.7℃ while January is the coldest season with average temperature being -2℃. The annual rainfall in Lhasa is 200 millimeters or so and mainly concentrates in June, July, August, and September. The best time to visit Lhasa is from April to October when daily temperature difference is smaller. It’s worth mentioning that night rain is common in this city.