Snow forms when the atmospheric temperature is at or below freezing (0 degrees Celsius or 32 degrees Fahrenheit) and there is a minimum amount of moisture in the air. If the ground temperature is at or below freezing, the snow will reach the ground. ... While it can be too warm to snow, it cannot be too cold to snow.

What is the reason for snowfall?

Air that is teeming with water vapor and moisture is said to be in a supersaturated state. Under this state, the water vapor condenses on the smoke and dust particles mixed in the air. Upon further cooling, it turns into snow particles. These particles combine with each other to form snow crystals.

What is the point of snow?

Snow helps insulate the ground below, holding in heat and preventing moisture from evaporating into the atmosphere. Even on top of other frozen material, such as permafrost and river ice or sea ice, snow cover prevents ice from forming as quickly.