The origin of light snow solar terms?

There is little snow, and there is no snow on the ground, which is the original meaning of the solar term "light snow"

The ancient book "Qunfangpu" said: "A light snow will snow when it is cold, but the ground is not cold and the snow is not heavy." In other words, due to the cold weather, the form of precipitation changed from rain to snow in the "light snow" festival, but at this time, because the ground is not very cold, the number of snows is small and the amount of snow is not large, so it is called light snow.