the weather pattern for snow fall in the US?

Question

why is it that sometimes it can snow at just about 4 degree celsius and sometimes it can get to even-2 but it would never snow,why does this happen?As when its about to rain and it becomes sooo cloudy and very humid,how does one know if it wants to snow?does it show any impending signals ans sighs before it snows,what are some?

Answer 1

Hi. It is just physics. Temperature and pressure and moisture content.