What weather is suitable for wearing knee socks?

The outdoor temperature is probably above 15 degrees and the air humidity is above 50%. There is no problem in sunny weather, but there is a question of whether the socks that go over the knees are thin or thick. The key depends on what you are wearing. What I just said is thicker, and if the weather is a little colder, you can wear another layer of socks underneath. The specific situation was analyzed in detail.