From the Summit Daily News (Paige Blankenbuehler):
The science behind snowmaking though brings many factors into play, but snowmaking officials base their operations mostly on temperature and humidity, a combination that provides them with a “wet-bulb temperature.”
“The drier the air, the more likely it is to be cooler,” said Mike Looney, snowmaking manager for Copper Mountain Resort. “We start at about a 28 degree wet-bulb temperature — that can be anywhere from 28 degrees and 100 percent humidity or as much as 35 degrees and 10 to 20 percent humidity.”[…]
The ideal conditions for snowmaking fall between a wet-bulb temperature of 10 and 20 degrees with consistent winds of approximately 10 miles per hour, according to Looney…
The formula for the wet-bulb temperature is based on humidity and temperature. Temperatures vary as humidity increases or decreases but typically it’s about one degree per 10 percent humidity, Looney said.
Copper Mountain uses water from Ten Mile and West Ten Mile Creeks for its snowmaking operations. The naturally cold water is ideal for sustaining operations through the season, Looney says…
As the water is cooled and comes out of snowmaking guns, the compression of the water paired with compressed air creates a smaller water molecule that freezes as it’s expelled from the nozzle…
Rapid expansion also creates the snowmaking properties of the water in the air mix. When the water reacts with the compression, it turns into a smaller molecule with a better chance of freezing once contacting outside temperatures. Copper Mountain’s snowmaking product includes an additive called SnowMax made up of live cultures that serve as an ingredient for the water to cling onto…
The rate of snowmaking is also reliant on outside temperatures. Snow guns in peak conditions for snowmaking can transform upwards of 2000-3000 gallons of water per minute into man-made snow…
“Man-made snow is getting way better with technology,” Looney said. “Our snowmaking crews are extremely conscientious about the product we put out. They are constantly checking the snow while the guns are running and if it’s too dense, too wet or too heavy, they make adjustments.”