The average altitude in Tibet is high, and the temperature varies greatly from morning to night. The climate in winter and early spring is dry and cold with blowing sand. The oxygen content is obviously lower than that in summer. So the best time to travel to Tibet » is from May to October.
The time from July to August is the rainy season in Tibet. Mudslides and landslides may happen in some places which can block the way for vehicles passing, especially in Sichuan-Tibet highway, the way from Lhasa to Nyingchi, and the way from Lhasa to Ngari. Though the scenery in Tibet is beautiful during this time, many people dare not to go. So, most people prefer to go to Tibet in May/June or September/October. Except for the rainy season, the period between May to October is the Tibet travel peak.
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