Is it hotter to go to Qinghai in early July than to Chongqing? Can I wear sandals?

I am very clear about this problem. First of all, I am from Qinghai. I came to Chongqing to study. Of course, the climate is not as good as Chongqing, and the ultraviolet rays are strong. It is necessary to use sunscreen reasonably. It is ok to wear sandals. It is recommended to wear long-sleeved clothes and trousers, otherwise a day's tanning is inevitable. In addition, in the case of dry climate, you can drink more water to relieve dryness. It is recommended not to go out at noon, because it is the hottest time of the day. Although the temperature difference between Chongqing and Qinghai is quite large, the climate is different and the heat generated is different. Have a nice trip to Qinghai ~ ~ ~