A warm spell in December used to mean a closed resort. That is rarely the case anymore. Most major ski resorts in North America now run extensive snowmaking systems that can cover hundreds of acres in a matter of days, regardless of what the weather is doing. The technology behind artificial snow has advanced far beyond the basic snow guns of the 1970s, and the systems running today are a significant part of how resorts stay open and competitive through the entire season.
Here is a plain breakdown of how ski resorts make snow, why the process works, and what it means for skiers on the ground.
Why Snowmaking Exists
Natural snowfall is inconsistent. Even resorts in traditionally high-snowpack regions have lean years. A resort that relies entirely on natural snow runs a significant business risk. A single poor December can wipe out holiday bookings, and a warm February can end a season weeks early.
Snowmaking solves the reliability problem. It gives resort operators control over at least part of their snow base, letting them open terrain on schedule and maintain conditions when natural snow is absent or thin. For visitors, that reliability translates directly into better odds of skiing on decent snow whenever they show up.
The relationship between snowmaking and climate is also becoming more relevant each season. As natural snowfall patterns shift, resorts with stronger snowmaking infrastructure hold a clear advantage over those without it. The broader picture of how climate is affecting the ski industry is covered in detail in the guide to climate change reshaping winter sports.
How the Snowmaking Process Works
Artificial snow is not frozen water sprayed into the air. The physics are more specific than that. Making snow requires water, compressed air, and temperatures cold enough to allow ice crystal formation before the droplets hit the ground.
The basic process works like this:
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Water is drawn from a reservoir or pond built specifically to supply the snowmaking system. Most resorts maintain dedicated water storage that holds millions of gallons.
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The water is pumped at high pressure through a network of pipes running under or alongside the ski trails.
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Compressed air is injected into the water stream at the snow gun. This breaks the water into very fine droplets.
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The droplets are launched into the cold air, where they freeze into ice crystals as they fall.
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The crystals accumulate on the trail surface, building up a base layer that groomers then pack and shape overnight.
The key variable in all of this is temperature. Snowmaking works most efficiently at temperatures below 28°F. At that point, the droplets have enough time in the air to freeze completely before landing. Warmer temperatures require more compressed air to compensate, which costs more energy and produces denser, heavier snow.
Types of Snow Guns
Not all snow guns work the same way. Resorts use different equipment depending on the terrain, the temperature, and how quickly they need to move snow onto a trail.
Fan Guns
Fan guns are the large, wheeled machines you see positioned at the sides of trails. They use a high-powered fan to propel water droplets across a wide area. A single fan gun can cover a large section of trail quickly and works well on wide-open runs where spreading coverage matters. Fan guns are loud and highly visible, which is why they are the piece of snowmaking equipment most skiers recognize.
Stick Guns
Stick guns, sometimes called tower guns, are fixed hydrants mounted on poles along the trail edges. They are smaller than fan guns and less flexible in terms of direction and coverage area. However, they run continuously without staff on site and form the backbone of most resort snowmaking networks. A resort might have hundreds of stick gun positions wired into its central control system.
Low-Energy Guns
Newer low-energy snow guns use less compressed air and draw less power while producing snow at similar volumes. Resorts have invested heavily in this equipment over the past decade as energy costs have risen and environmental scrutiny of resort operations has increased.
The Role of Water and Energy
Snowmaking consumes two resources in large quantities: water and electricity. Both have become central to how resorts plan and defend their snowmaking programs.
A single snow gun can use between 50 and 150 gallons of water per minute. A resort running dozens of guns across multiple trails over several nights draws a substantial amount from its water supply. Most resorts have moved to closed-loop or reclaimed water systems where melt from the snowpack returns to the storage pond and gets reused the following season.
Energy consumption is the other major factor. Running compressors, pumps, and fan guns across a large resort requires significant electrical capacity. Many resorts have responded by shifting snowmaking operations to off-peak hours when grid demand is lower, and by investing in more energy-efficient equipment.
Killington Resort in Vermont operates one of the largest snowmaking systems in North America, covering over 600 acres of terrain with more than 1,900 snow guns. Killington regularly opens terrain in October, well before natural snow arrives in the region. The Killington ski resort poster maps out that full mountain, showing the scale of terrain the snowmaking operation supports each season.
What Snowmaking Means for the Ski Season Calendar
Snowmaking directly affects when resorts open and how long they stay open. Without it, most resorts in the eastern United States would not be viable at all. The natural snowfall in states like Vermont, New Hampshire, and Pennsylvania is too variable to support a consistent ski season without supplemental snow production.
In the West, the calculus is different but still significant. High-snowpack resorts in Utah and Colorado receive far more natural snow than their eastern counterparts, but they still rely on snowmaking to open early season terrain and protect base layers during warm spells.
For skiers planning a trip, knowing a resort's snowmaking capacity helps set expectations. A resort that can cover its entire beginner and intermediate terrain artificially will have skiable conditions even in a low-snow year. A resort with limited snowmaking may have terrain closures that affect the visit significantly. For a broader look at timing, the guide to best time of year to ski or snowboard breaks down how natural snow cycles interact with the resort calendar across different regions.
How Grooming Works with Snowmaking
Artificial snow straight from the gun is not the same texture as groomed snow. Fresh machine snow is often coarser and denser than natural powder. Grooming machines, the large tracked vehicles that work the trails overnight, blend and compress the artificial snow into a consistent surface that skis well by morning.
The grooming process also helps the snowpack bond. Loose artificial snow on a trail can shift and thin quickly under heavy traffic. Grooming compresses the crystals so they interlock and hold up better through a full day of skier traffic. On high-use runs, groomers may work the same trail multiple times in a single night.
Breckenridge in Colorado uses a combination of natural snowfall and aggressive snowmaking to maintain its terrain from November through late April. The resort's high base elevation, over 9,600 feet, means groomed artificial snow holds well even through warmer spring days. The Breckenridge ski resort poster shows the full spread of terrain that benefits from that snowmaking and grooming combination.
Artificial Snow vs. Natural Snow
Skiers notice the difference between groomed artificial snow and natural powder. Machine snow is denser and harder. It holds an edge well, which makes it predictable and forgiving for beginners. But it lacks the lightness of fresh powder, and a heavy snowmaking night can leave trails feeling icy in spots before the grooming pass smooths things out.
The best ski conditions usually come from a combination of both. A solid artificial base with a layer of natural snow on top skis better than either alone. Resorts aim for that combination whenever the forecast allows it.
Keeping the Mountain Open
Snowmaking is now a core part of ski resort operations, not a backup plan. For visitors, it means more reliable access to terrain across a longer season. For resorts, it represents a major infrastructure investment that shapes everything from opening day to the final weekend of spring skiing. Browse the full range of ski resort posters at Powder Goods to find a print from the mountain that first showed you what a well-groomed run actually feels like.