Nothing affects the success of a skiing or boarding holiday quite as much as the quality of the snow. It is actually the quality that matters most, but in practice you will find a lot of emphasis is put on the quantity, because it's much easier to assess and the two tend to go hand in hand.
If snow is in short supply, that means the snow on the ground will be thin (so there will be rocks poking through) and probably hard. If snow is abundant the runs should be completely covered, and there is at least a chance that some of it fell quite recently and is still soft and fluffy, which is better.
In the last two decades, dependence on real snow has been greatly reduced by large installations of snowcannons designed to create an artificial substitute. If made carefully and "groomed" skilfully, artificial snow can provide an impressively rewarding piste surface. This is regularly achieved in many American resorts, and the European resorts have improved and increased their snow making capacity in recent years. Most large resorts in the Alps have the means to keep many of their runs open in weather conditions that would previously have closed them.
Snowmaking is mainly of value in the earlier part of the season (though there are American resorts that make such a depth of artificial snow in winter that they can create mini-glaciers on which skiing and boarding can go on into high summer). It requires quite low temperatures. Many American resorts are able to open in November or early December only because of snowmaking.
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