The Sawtooth National Forest Avalanche Center has barely opened its doors for the season, but staff said this week that avalanche danger has already hit the region.
Chris Lundy, the center's executive director, said he triggered a slide on Titus Ridge north of Ketchum on Friday, as well as spotting several natural slides.
"It's earlier than normal, but it all depends on how much snow there is on the ground," he said Monday. "But if there's enough snow to ski or ride, there's enough snow to avalanche."
Early October snow that remained on shady slopes has already formed the region's characteristic persistent weak layer, a layer of unstable snow that can cause a slide.
Lundy said this weak layer is likely to appear in avalanche advisories all season, as this characteristic of the regional snowpack causes multiple avalanches per year.
This isn't true for all mountainous areas nationwide, he said, especially those closer to the coast in the Cascades and Sierras.
"They might get more snow per storm, and the avalanche danger will be high for a day or two and settle out," he said. "We can get a smaller storm, but then [the weak layer, and the danger] just stays."
Daily avalanche advisories are expected to start on Saturday, Dec. 3
"Historically, that's when we've had enough snow," Lundy said, "Though there are a few hardy folks getting out right now," which is why the center has begun releasing general snow and weather advisories on an as-needed basis.
Last year the weak layer was particularly persistent, Lundy said, due to several dry spells that allowed the top layer of snow to "facet," or turn sugary. Once several inches fall on that weak snow, conditions are ripe for a slide.
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Despite risky conditions, there were no fatalities last year.
"Certainly we had some close calls, and maybe we just got lucky," Lundy said. "But we saw a lot of people using their heads last year and making good decisions."
The center will issue daily advisories via email and online at 7:30 a.m. seven days a week. Information will also be available by calling the Avalanche Advisory Hotline at 622-8027, or by tuning into KECH radio at 7:45 a.m. each morning.
This year, the center will also continue posting urgent advisories on Facebook and Twitter.
The center will hold its traditional avalanche awareness classes throughout the winter for all backcountry adventurers, but with two new offerings this year. Lundy said last year's exposure of the extent of sidecountry or out-of-bounds skiing on Bald Mountain led to the center's offering a class geared toward those skiers.
"Even though [out-of-bounds skiers] are still on skis, it's a very different sport," Lundy said. "Most of these people aren't going to come to our backcountry avalanche class."
The sidecountry class will be held in conjunction with the Sun Valley Co., and will follow a slightly different format from the center's other seminars. The class, held Jan. 21, will start with a two-hour classroom session on avalanche basics and using an avalanche beacon before participants head up on the mountain for field work.
Lundy said participants will learn to evaluate avalanche terrain, dig snow pits to test snowpack stability and practice mock avalanche rescues.
The other new offering is mainly a change in location, as the center will offer a class geared toward snowmobilers in Carey. Though there are similarities in the classes, Lundy said snowmobilers face particular challenges.
Snowmobilers must be more alert, Lundy said, because they cover a larger amount of terrain than skiers typically do, switching from slope to slope and possibly running into more isolated pockets of high-risk snow.
Still, no matter the sport of choice, Lundy said, knowledge of avalanche risk is crucial for anyone heading into the back or sidecountry.
"The danger is the same, the mountain is the same, the snowpack is the same," he said. "What's different is how they approach evaluating the danger."
Katherine Wutz: kwutz@mtexpress.com
Risky business
Here are the telltale signs of avalanche danger in the backcountry. Recreationists should keep an eye out for:
- Recent natural avalanches.
- Cracking or collapsing of the snowpack.
- Recent "loading" of slopes due to wind-blown snow or new accumulation.
- Rapid warming or temperature changes, which can destabilize the snowpack.