All moisture has frozen and snow is almost lighter than air. Snow is also very dry now and it's impossible to form any constructions out of snow with traditional methods. Freshly fallen snow is maybe the finest material in the world, but it easily turns to hard and thick material. When directing pressure to snow, it becomes excellent building material. Compressed snow can be compared to light concrete and ice to concrete.
Snow is still weaker than ice, but snow has better workability and it insulates heat better.
Unfortunately, it sometimes does not snow exactly when we want it to, or when we need it to.