Wyoming here. in the midst of the cold part of winter...even at 30 below,,,on a sunny day you can watch just over the top of snow and see the water in a gaseous state. Quite often what happens here is it gets up to 15-20 below then at night getting colder again you can see that moisture in the air turning to ice crystals and falling...not as snow really but you can feel it...almost like really cold fog...yep....sublimation...not well understood though by the average person