The climate in highland Tibet belongs to the typical downy special climate. Climates are much different in different areas in Tibet and temperatures vary greatly within a single day. Climate in southeastern Tibet (e.g. Nyingchi) is gentle and temperate with the average temperature of eight degrees; In western Tibet (e.g. Nakqu), the average temperature is below zero degree; While in Lhasa and the central part of Tibet, the climate is normal and nice for traveling. Visitors would not feel cold in winter nor hot in summer, especially from March to October, the best seasons for traveling. Most annual rainfall comes in the rainy season that starts from May to September, when the precipitation covers 90 percent of the whole year. Usually it rains at night in Lhasa, Shigatse and Chamdo area. The precipitations gradually decrease from 5000 millimeters in the lower part of southeast to just 50 in the northwest.