What is the best time for travel to Tibet?

Generally speaking the best time to travel around Tibet is from April till September. Tibet, being a Trans-Himalayan region, receives much less rain in the summer, with exceptions of those areas in southern Sichuan and Yunan. From October onwards, the temperature drops significantly and starts snowing in high passes and places in higher altitudes. However Tibetan areas, particularly the south is not as cold as one tends to imagine. Even in winter, in most places, snow hardly stays on the ground for more then one night. The sheltered valleys of Lhasa, Shigatse, Tsetang and southern Kham (areas south of Sichuan and Yunan), the winter days are mild and beautiful.