What's the weather like in Tomb-Sweeping Day and Beijing? Is it cold to go to the Great Wall?

Before Beijing No.3, 15 and 16 degrees, and within 10 degrees in the morning and evening. I wonder if it will go up a little in the next few days. The temperature of the Great Wall may be several degrees lower than that of the city. If you go to the Great Wall, prepare an extra coat. This extra dress had better be easy to wear without affecting the collocation of other clothes. If the temperature changes, it is easy to adjust the height, and there is no need to climb the Great Wall back to the city.