Getting first tracks at a large western ski resort like Big Sky, Vail, or Jackson Hole is always the highlight of my winter. The steeper the slope and the deeper the snow is, the better. One time on a trip to Snowbird, a storm dumped six feet of snow in 24 hours. The two-lane road to the ski area closed due to avalanche danger. Guests staying at the mountain had to remain indoors while the sounds of explosives reverberated around the resort. The blasts delighted those of us who were stuck inside. We would get several runs in the virgin snow when lifts reopened, before anyone else arrived.

Eager to sample the pristine powder, I joined the small, eager throng at the base of Snowbird’s tram when word came that the resort was ready for skiers again. I headed straight to Mineral Basin, with its 500 acres and 1,300 vertical feet of wide-open terrain, and skied for two hours before the crowds showed up. I hooted and hollered as the fluffy flakes skimmed my thighs and sometimes my shoulders. The possibility of getting caught in a deadly avalanche never crossed my mind. After all, the ski patrol had done their part to prevent avalanches from burying guests like me, and I was within the ski area boundary on a well-known slope. Was I naïve?

Playing the Odds

“There’s always inherent risk when skiing,” said my son Parker Densmore, who has worked as a professional ski patroller at Park City Mountain Resort in Utah for the last seven years. Based at The Canyons part of the ski area, Parker leads a team that sets off avalanches on purpose, before the lifts open, to prevent them from happening when skiers and snowboarders are on the slopes. He’s also an avalanche dog handler. In other words, he helps mitigate the chances of an unwanted slide, but if it does happen and someone gets buried, he can help find the victim.

Avalanches within ski area boundaries occur more often than you might think. For example, in late November 2023, a huge slab of snow 1,000 feet across barreled down four closed trails at Steamboat Resort in Colorado. Luckily, no one was injured. When a “slab avalanche” like that cuts loose, it’s extremely dangerous. It can travel at 80 miles per hour and snap mature trees as if they were matchsticks. Sometimes they are triggered by skiers, and sometimes they are triggered naturally due to heavy snow or wind, often in conjunction with rapidly warming temperatures.

By coincidence, at a 2023 international snow science workshop in Bend, Oregon, snow experts from Washington, Idaho, Montana, and Colorado presented the results of their collaborative research in the paper “Characteristics of Inbounds Avalanche Fatalities at United States Ski Areas.” According to their findings, the risk of a skier or snowboarder dying in an avalanche at a ski area in the United States is one in 60 million skier visits, or about one person per winter. In fact, over the last two decades, 17 people have died in 14 inbounds avalanches. These accidents typically occurred when terrain opened for the first time for the season. What’s more, the terrain had already been controlled by the ski patrol, but a weak layer of snow persisted, and there were multiple people on the slope.

“Our snow team does its best to prevent inbounds avalanches,” said Parker, echoing the research. “The biggest risk occurs when opening new terrain. That’s when the snow is most likely to have a weak layer, especially if it snows in November and not again until December. Then you’ve got old, faceted snow under new snow.”

Faceted snow is ski patrol-talk for what most skiers call sugar snow. The snow crystals are large, angular, and weakly bonded. You can’t form a snowball with it. Temperature swings contribute to faceting, another reason why the early and late ski season are particularly avalanche prone.

“When facets are in the snow structure, the snow crystals are like a house of cards,” explained Parker. “They’re fragile, and if they collapse, there’s an avalanche.”

A First-Hand Look

Two winters ago, I went to Park City for a ski vacation because it was also a chance to visit my son. It was a memorable trip. He knew where to find the hidden stashes of powder when the rest of the mountain was skied out, and he taught me a few things about snow control.

At one point, he took me to the top of Ninety-Nine 90, the highest point at The Canyons. From there, we traversed past several steep chutes to one of those secret spots. “What are the ropes for?” I asked, pointing to several sturdy red ropes strung anywhere from waist high to above my head down several slopes. “Trams,” replied Parker. “Obviously not for skiers to ride,” I deadpanned, remembering that glorious day at Snowbird. “It’s for dynamite,” continued Parker. “Sometimes a charge gets thrown onto the snow, and sometimes it’s better to suspend it on a tram, causing a compression from above to trigger a slide.”

“Dynamite?” I asked, feeling a twinge of anxiety about my son’s hands-on work with explosives. “I start my morning building the bombs,” he replied. “Then I ski my route. My partner and I climb up to a ridge, then we either throw them or send them down a tram. They’ve got a two-minute fuse, so plenty of time to duck over the other side of the ridge or get behind a big rock.”

My brain five-alarmed at the thought of my son getting behind a rock to avoid getting blown up or getting swept down a slope with multiple tons of snow. Parker sensed my distress.

“Don’t worry, Mom,” he said, “We don’t always use explosives. The resort’s forecasters show up at 3am. They look at the weather stations on the mountain to assess the accumulated snow and wind. Four inches of snow with high winds can be a bigger problem than eight inches of snow and no wind.”

According to Parker, wind increases avalanche danger due to “wind loading.” In other words, the wind moves snow, typically from exposed slopes to sheltered ones, which can create a wind slab—heavy, dense snowpack with a weak layer underneath. Significant wind loading means high avalanche risk.

“It’s the trends that are important,” said Parker. “Is there a persistent weak layer or a new snow problem? Then we decide what needs to be done, explosives or zaws.” Zaws, also called ski cutting, is another ski patrol term for essentially zigzagging back and forth across a slope. Ski patrollers in the Northeast cut steep slopes, too, typically on trails that are difficult to groom or when the base is not deep enough for a grooming machine to work the snow.

As Parker and I talked, I calmed down, only to get ramped up again a moment later, this time in a good way. We had arrived at the trail that he wanted to take me down. The entrance was narrow, a mere swath of snow between tall alpine firs that plummeted below my ski tips. Even though the snow had fallen two days ago, it was still dry and untouched.

“Parker, not to change the subject, but you know what they say about skiing powder. Don’t be last!” With that I pushed off, but Parker didn’t hesitate. “No friends on a powder day!” he laughed, arcing a turn beside me as we cleared the trees onto a wider piste. Then he sprayed me on his next turn as he pulled ahead, but the spray was merely white dust as I skied through it. The snow in Utah is often called champagne powder because it’s so light. Each turn tickles you from head to toe, like taking sip after sip from a glass of fine sparkling wine. When we stopped at the bottom, I could hardly wait to do it again.

My worries about my son building bombs to set off avalanches still occasionally creeps into my mind, but another part of me is grateful for the work he does, so skiers like me can play in the powder on our ski vacations. 

SIDBAR

10 Ways to Ski Smarter in Deep Snow  

Are you a powder seeker heading west for 

a ski trip this winter? These tips will lessen your risk of getting buried in an avalanche and other causes of serious injury in deep snow:

1. Obey the signs. They tell you where it’s safer to ski. Things might have changed since the last time you were there.

2. Never jump a rope. The snow may look tempting, but the slope might be avalanche prone, or there might be obstacles underneath the snow or a cliff.

3. Know your location, especially if you go through a gate. No one can help you if you don’t know where you are and whether you are within the ski resort’s boundary.

4. Check your bindings. Your skis should come off if you crash, if you are caught in an avalanche, or if you fall into a tree well (see below). If you’re worried about losing a ski, consider tying a length of surveyors tape to the heel piece of your binding to help you find it in powder.

5. Remove your ski pole straps. You’ll save your shoulder if your ski pole basket gets caught on an unseen obstacle under the snow.

6. Give trees a wide berth. “Tree wells” are hidden, snowless voids around the trunks of large evergreen trees. The lower branches of the tree prevent snow from accumulating next to it. It’s difficult to get out if you fall into a tree well, and you might suffocate.

7. Ski with a buddy. You might need help getting up and finding your gear after falling in deep snow or if you get stuck in a tree well. Your buddy can always go for help if you’re stuck or seriously injured.

8. Leave your ego at home. You may be an expert on hardpack at New England ski areas, but deep snow requires different techniques and tactics.

9. Slow down. Just because you’re an ex-ski racer doesn’t mean you won’t get hurt if you make a GS turn into a buried stump. While it’s fun to make fast powder runs, take it a little slower so you can ski the next run.

10. Go fat. While all skis can get down a powdery slope, fatter skis give more buoyancy. Rent them at the resort if you don’t own a pair that are at least 90mm in the waist or wider.