In fact, the Tibetan climate is not as harsh as many people imagine it to be. It is suitable for travel to Tibet from April to the beginning of November, and the best time is August and September. But if you only stay in Lhasa, you can go there any time of the year.
Sun radiation is extremely strong in Tibet. The sunlight in Lhasa is so intense that the city is called Sunlight City. The thin air can neither block off nor retain heat so that the temperature extremes can be met in daytime and the same night respectively in Tibet. However it is not impossible to visit the holy snow land. May, June and September are the tourism season in east Tibet.
Most annual rainfall comes in the rainy season that starts from June to September. Usually it rains at night in Lhasa, Shigatse and Chamdo area. The rainfall may block roads and make travel difficult but the scenery at the time will be the best.
China's climate varies from bitter cold in winter to unbearable heat in summer.
The Yangtze River serves as China's official dividing line between north and south. Given the size and varied landscape of the country, there is no one time in the year when weather is ideal in every part of China. Of course, the warmest areas in winter are to be found in the South and Southwest, such as Sichuan, Banna in Yunnan, and Hainan Island. In summer the coolest spots are in the far northeast.
China has a climate dominated by dry seasons and wet monsoons, which leads to clear temperature differences in winter and summer. In winter, northern winds coming from high latitude areas are cold and dry; in summer, southern winds from sea areas at lower latitude are warm and moist.
China climates differ from region to region because of the country's extensive and complex topography. In the south of the Nanling Mountains, rains are prolific and the temperature is high all year round. In the Yangtze and Huaihe river valleys in the central part of China, there are four distinctive seasons.
In northeast China, summer is short but there is much sunshine, while winter is long and cold. Precipitation is limited in northwest China where it is cold in winter and hot in summer. In southwest China of low latitudes, the land is elevated high, and has characteristically vertical seasonal zones.
High season marks the most popular times of the year for travel in China, due to the weather, holiday periods or other reasons. Therefore hotels, airlines and travel agencies are heavily booked, and prices are higher than usual.
The seasons are usually defined as follows:
High season: April 1 to May 31, Sep 1 to Nov 15.
Shoulder season: June 1 to Aug 31.
Low season: Nov 16 to Mar 31 of next year.
However, there may be some variation to these dates by different hotels, airlines or travel agencies in different regions. For example, high season in Tibet is from July 1 to Oct 15 and the rest of the year is considered to be low season.
Travelers should also be aware that the peak holiday periods: first week in October, Chinese Spring Festival (often takes place in late January or early February) is particularly busy. Prices and bookings will be even higher than usual.
While China is a year-round destination, the months of April, May, September, and October are ideal months for travel anywhere in the country. In the north, the winters are cold, and summers are warm, with moist monsoon air streams making it hot (70% of China's rainfall occurs in late May and early October, mostly in the Southern regions). June through August is also a good time to visit central and northern China. Spring and autumn are the best months for travel across the country. The duration of November 16 -- March 15 is the lower-priced season; while the lowest price, off-season travel, is formed for adventuresome travelers with unbelievably low prices and far fewer fellow tourists.
