Killer avalanche hot spot in Idaho reveals forecasting gaps

This story was originally published by High Country News and appears here as part of the Climate Desk collaboration. This story was produced in partnership with Boise State Public Radio.

In 2019, a snowmobiler climbed a steep, south-facing slope in the backcountry near the Idaho-Wyoming border reaching for the ridgeline. But as he circled back down after a second attempt, the slope suddenly failed. A large avalanche caught him as it barrelled down the hillside. Shortly afterward, other riders in his group heard the chugging of his snowmobile under the debris. They found their friend, his helmet packed with snow, and attempted CPR, but he did not survive.

In the same area the next year, a professional snowmobiler died while riding in a group of 10. The following year, two teens — one riding a snowmobile and the other on skis — were killed in a slide on a steep, wind-loaded face.

Eleven people died in avalanches in eastern Idaho between 2016 and 2021 — an unusually high rate for the number of people who recreate there. Ethan Davis, an avalanche forecaster at the Sawtooth Avalanche Center in Ketchum, Idaho, wanted to know why. The National Avalanche Center did, too, and enlisted him to find out. Davis studied the accidents and their victims. Most were snowmobilers; several were not wearing an avalanche transceiver or it wasn’t turned on.

But another factor kept creeping up, too. “We realized that we don’t have an avalanche forecast centre in eastern Idaho,” Davis said. Though four avalanche centres — in Utah, Montana, Wyoming and central Idaho — surround the area, there’s no centre dedicated to assessing hazards in the eastern part of the state. It’s a doughnut hole of unknown danger, where lack of information is costing lives.

There are 23 avalanche centres in the U.S., 14 of which are jointly funded by the Forest Service and affiliated non-profits. They employ forecasters who visit the mountains and dig holes in the snow, searching for signs of instability. The forecasters distill their field notes and community observations into advisories that signal the likelihood of triggering an avalanche in specific mountain ranges or at certain angles and elevations.

Many centres emerged in the 1970s, ’80s and ’90s in traditional recreation hubs like Jackson Hole, Wyo., and Salt Lake City. But the Mountain West has grown tremendously since then, pushing people to access the outdoors in new places and new ways — a trend that was supercharged by the pandemic. Meanwhile, avalanche centres’ maps have remained largely static, leaving the region dotted with doughnut holes, including mountains near Boise, the area between Missoula and Butte, Mont., and ranges in southern Wyoming and southern Oregon.

IN THE PARKING LOT of a trailhead near Driggs, Idaho, earlier this winter, a group of snowmobilers gathered for the second day of an introduction to avalanches course led by the Mountain Riding Lab, an avalanche school that specializes in motorized recreation.

Tayler Anderson pulled up with her blue, pink and leopard-printed sled. She signed up for the training after a rider she knew — the professional snowmobiler caught in an avalanche in 2020 — died. “Just losing people close to you opens your eyes,” she said.

Anderson, from Challis, Idaho, noted the mountains near Driggs are not covered by an avalanche forecast. Yet backcountry snowmobiling is booming here, partly because improved technology allows the machines to reach formerly inaccessible terrain.

Will Mook, co-founder of the lab, urges his students to check the daily weather and avalanche reports from the centre across the Wyoming border. But information from that area doesn’t always reflect conditions here: They won’t know exactly what’s going on in the snow until they’re out in the mountains.

Mook, who sports a scruffy beard and affable attitude, said that when he wakes up, he pours a cup of coffee and reads the forecast for Wyoming, where he often rides. It’s ingrained in his routine. As a result, he knows what hazards to expect and what terrain to avoid — that day, and over the course of a season. Mook thinks studying the forecast would be routine for eastern Idahoans, too, if there were more information about the mountains they frequent.

Closing that doughnut hole could come from expanding the resources of the nearest avalanche centres: Most of the deaths Davis analyzed were very close to, or even just within, neighbouring forecasting areas. A working group from those centres hopes to see forecasters based on the ground in eastern Idaho to provide localized information, educate the community and build trust.

Mook agreed that this would help. Ideally, he said, they’d be die-hard snowmobilers. The question is where to find the money; most centres’ budgets are already strained. “I would say almost every single avalanche centre in the United States is struggling with this,” said Simon Trautman, director of the National Avalanche Center. “Do we need to adjust our boundaries? And, if we do, what does that mean? And how do we fund it?”

Whatever solutions the group identifies could become a blueprint for other spots in the Western U.S. where more people are exploring the backcountry, ultimately providing information that could save a lot of lives.