It is still cold to wear four clothes at 20 degrees.

The weather at 20 degrees is not very cold. Generally, it is enough to wear a bottoming shirt and coat outside. But some people are afraid of the cold, so it is ok to wear more. Under the temperature of natural weather, the south doesn't feel cold at 20 degrees, and the north still needs to wear some warm clothes. Wearing four clothes at 20 degrees still feels cold. You can go to see Chinese medicine and prescribe some medicine to tonify yang.