Tibetan time is the same as Beijing time because a single time zone is used throughout China:GMT + 8 hours (Beijing time). This leads to long daylight hours in the evenings and dark early mornings. The boarder crossings between Tibet and Nepal or Xinjian and Pakistan are the only places you may potentially be jet lagged if traveling inside China.
Technically, Lhasa should be on the same time zone as Nepal (2 and a quarter hours behind Beijing) but due to China’s centralized time is running on time with a city thousands of miles away. For example if you fly out of Kathmandu into Lhahsa you’ll have actually arrived before you left, time-wise. Nepal is 5 hours and 45 minutes ahead of GMT and Bhutan is 15 minutes ahead of Nepal.
However, a lot of Tibetans just run on Tibetan time, meaning a step back into a timeless arrangement where they get up when the sun rises and go home when the sun goes down.
The best time to visit Tibet is in early spring or late autumn meaning April to June or September to November. Summers are usually too wet, while winters are too cold for the majority of travelers. June through September in Lhasa can be nice all the way until the end of December but at night the temperature drops dramatically. During cold months, many nomads come to Lhasa and with few tourists presents this is often the most interesting time to visit. Generally, western Tibet is drier while the eastern part is affected by Southeast Asia’s weather patterns leaving the plateau rather wet during August.
Spring (March-May)- Tibetan springs are typically short, cool, dry and dusty but have great clear skies for sightseeing. Excessive wind and sandstorms can make travel difficult.
Summer (June-August)- This is the wettest season which causes rivers to flood, and is usually cool and wet but hot by noon. This season is the rainy season and has a 70-95% chance of annual precipitation which causes snow on the hills and night rain in valleys. Flash floods and high rivers can disturb the already poor road conditions. Most of the rain falls in July and August and snow is not common in the lower altitudes. However, the weather still tends to be dry with lower humidity. The hills are green and the temperature is mild. Temperature can vary by seasons so bring extra layers of clothes.
Fall (September to November)- These months are cool and dry as rains typically have ended by late September and rivers begin to recede. Days are hot and sunny in the beginning but towards the end of the season look out for cold nights and snow.
Winter (December-February)- This season is cold and extremely dry. While there is no rain or sand to obstruct vision, it's too frigid to be outside for exceptionally long periods without proper equipment. During this time the Lhasa airport is usually closed and high mountain passes on the roads become impossible to cross.
Pamela Riis