Grooming by snowcats pushing and tilling the man-made snow is an important element in providing good skiing. While the snowmaking guns are moved frequently, there typically will be piles left in front of each gun which must be graded into a smooth, relatively flat surface before operations. After a good period of snowmaking some of these snow mounds may be as big as a small bus and are called ÒwhalesÓ by the crew. After the new snow is spread evenly, the surface is gone over with a tiller on the back of the cat, which is a sort of grinder that pulverizes the top 3 to 6 inches of the snow to give it the ideal texture for skiing or boarding. Grooming is a real art to know when and how to push the snow around and condition it into a good grippy surface preferred by skiers and snowboarders. Fresh man-made snow is nearly always groomed into a consistently good surface prior to opening.

Santa Ana Winds

As mentioned above, dry air (low humidity) is very helpful to snowmaking and actually is as important as temperature. It allows, through evaporative cooling, more water to be converted into snow than does moist air at the same temperature. Believe it or not, the resorts can make very good snow in bone dry air with the temperature at 35°, yet struggle at 25° in a cloudy, foggy atmosphere.

Everyone knows Santa Ana winds are dry, but what many don't realize is that they are usually cool – sometimes very cold – as they come out of Utah and Nevada. These winds are heated by compression when they enter the valleys of Southern California. So, even though it may be beach weather in the cities, they are usually very good for snowmaking.