Snow already decays in less than a day once it's off a mountain top, because duh it's snow.
Why is it that cold compresses, the only useful use for snow, do not decay in a similar amount of time? It seems a little silly given that players are undoubtedly just converting all of their snow into compresses as soon as they get it. Cold compresses should decay, because they will no longer be cold when the snow in them melts. They'd just be compresses.