Well, I assume it would be snowing.
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.
So, to be exact. It will be snowing since the temperature in the atmosphere is below freezing and the snow will reach and stay on the group since the ground is also below freezing.
Hope this helped :)
