Ski resorts have relied on artificial snow–superfine ice, really–for decades. But traditional snow-making systems–which blow water and compressed air through special nozzles to aerosolize it, then rely on outdoor air to freeze it before it hits the slopes–only work when temperatures drop below freezing. Temperature-independent systems reverse that process. The machines freeze water inside a refrigerated compartment, pulverize the ice, then blow the “snow” out of a tube. Yes, some of it melts on warm days, but pile it up quickly enough and it self-insulates, allowing it to last surprisingly long. The downside: warm-weather snow makers start at about $500,000 and use lots of electricity.

As you’d expect from a start-up whose mission requires battling Mother Nature, progress has been slow. SnowMagic president Albert Bronander first saw warm-weather snow makers while working as a consultant in Japan in the ’80s. In 2001 he teamed up with Dan Eagan, a former extreme skier, and a year later they bought Tenney Mountain in Plymouth, N.H. After importing their first snow maker last summer, they pumped out enough snow to open a small, 370-foot by 10-foot slope on July 4, despite 90-degree heat. More than 200 skiers and snowboarders–mostly adventurous young’uns–gave it a try.

Over the next two months a narrow 300-foot tubing track was covered with snow –and 4,000 riders paid $20 apiece for two hours of sliding. Thanks to the machine, which can make 50 tons of snow in 24 hours (at a cost of about $300 per day), Tenney opened a single slope for skiing in early October, more than a month before most resorts. While his machines will never replace traditional snow guns when temperatures drop, Bronander says they could help many U.S. ski areas extend their season–and make skiing more viable in places like Virginia and South Carolina.

Until costs fall dramatically, though, the concept will remain a tough sell. Warm-weather snow making is popular in Japan because most ski areas are smaller, ticket prices are higher and the climate is so warm that it’d be hard to keep trails white without the high-priced gear. In the United States, cold temperatures allow ordinary snow guns to work most of the winter, so it’s harder to make a business case for the pricier systems. Cold-weather snow-making companies say the upstart’s equipment costs at least five times as much as theirs; some claim operating costs are 20 times higher. They also say that many ski areas, whose profits slalom from season to season based on the weather, couldn’t afford to invest millions in warm-weather snowmaking. Says Charles Santry of Snow Economics, which sells traditional snow guns: “There’s something appealing about eliminating the need for [cold] temperatures, but what brings you back down to earth is the energy costs.”

But SnowMagic, which now has 14 year-round employees, is undeterred. Last fall it made its first sale to an amusement park, in Kent, England, where Brits spent four months schussing down a small hill, holding kids’ birthday parties and having snowball fights. Next month the firm will deliver a system to a Saudi Arabian shopping mall, which will create an indoor snow park. Next fall Bronander will install a snow maker in a minor-league baseball stadium in Mobile, Ala., where Southerners will be able to learn to snowboard. By the end of the decade, the company hopes, snow areas will be a standard feature at major theme parks. Even skeptics concede that SnowMagic’s gear could be great for niches like this. As for its chances of revolutionizing the ski industry, for now it looks like an uphill climb.