The average temperature in Nyingchi in August is of about 12-22 degree Celsius. Although August is the rainy season in Tibet with bountiful monsoon, it normally rains at night. There is not much rain during the day with strong sunshine and UV radiation. Please remember to have sun protection when you travel. Nyingchi in August feels very comfortable with sufficient oxygen in the air and it has become a "summer resort" for many people. On the contrary it is very hot in the mainland China at this time. In the evening, when it occasionally rains a little in Nyingchi, it helps you to sleep better at night.
Nyingchi area is of a lower altitude. During the day, the sunlight is so strong that neither air conditioner nor fan is needed, which makes indoors feel comfortable. Sun protection is needed when you go outdoors. It is recommended to wear light long-sleeved tops and pants during the day, especially the loose ones which are easy for you to move around. Short sleeves and shorts are not recommended unless you want to get tan. It usually feels cool in the morning and evening. If it rains a little at night, you can just add a light jacket.
Daytime average temperature: 22°C, light cotton or linen clothes such as sports T-shirts/pants, jeans, light jackets, etc. are recommended.
Nighttime average temperature: 11°C, warm clothes such as wind breakers, thin sweaters, sports jackets, suits, etc. are recommended.
Nyingchi dose not only looks good when the peach blossoms blooming. The summer in Nyingchi is always with a small breeze around 20° C, and there are not many tourists. Mount Nanga Bawa is playing hide-and-seek in the clouds. Lulang Forest Sea, Bomigang Spruce Forest, the secret lotus flower Motuo are green everywhere with the clouds steaming and fogging. Various flowers and plants in Nanyi Valley are flourishing and blooming.
Because of the strong UV radiation, no matter which season you pick to travel to Tibet，sun protection is necessary.
The temperature difference between day and night can be really large in Tibet and you are recommended to be aware of it to stay well. Catching a cold can be dangerous due to high altitude complications.
When you first travel to the Tibetan Plateau, most people will feel different levels of hypoxia such as chest tightness, difficulty breathing or other symptoms. But this does not mean that you cannot adapt to the high altitude environment. If you can adjust yourself properly, the above symptoms can generally be improved or disappear in 2~3 days.
August is the peak season for travel to Tibet. It is recommended to plan and book your hotels and plane/train tickets in advance, since the accommodation and tickets can be difficult to get. Even a ticket for visiting Potala Palace may be really hard to book then.
August is also the rainy season in Tibet. If you are hiking to Ali and Medog, please be aware of the possible natural disasters such as landslides and mudslides. It is recommended to know the local weather before you set off.