HELENA - The winter of 2014-15 started out to be a pretty good one for Doug Chabot; by Jan. 5 there had been only one fatality from avalanches in Montana.

Chabot is the director of the Gallatin National Forest Avalanche Center, based in Bozeman.

But on the day Chabot was interviewed, the avalanche danger rating had just been bumped up from “moderate” to “high.” When the danger is “high,” backcountry travel is “very dangerous” and “travel in avalanche terrain is not recommended.”

There is only one higher rating on the avalanche danger scale: extreme. Extreme danger means large and very large avalanches are a certainty.

The setup for the current dangerous conditions had started on New Year’s Day, Chabot explained, when the nice weather had resulted in a deposit of “surface hoar,” a crystalline deposit of dew. Surface hoar, Chabot said, looks like small feathers standing up. Surface hoar is easily collapsible, and with the snowfall that started on Jan. 4 conditions were ripe for an avalanche triggered by a collapse. “Once buried, it (surface hoar) becomes an avalanche problem,” Chabot said. “The weight of a skier or a snowmobiler can easily get these things to trigger.”

The snowstorm that started the fourth day of the new year and was forecast to continue for several days was adding a particularly dangerous coating. Not only was it deep, it was also heavy. Many of the mountainous areas in the western area of the state had already gotten two feet of wet snow Monday and the forecast was for another foot or more by the time it was expected to clear Wednesday.

Of particular concern to avalanche experts like Chabot is the weight of the snow. Avalanche experts express the weight of the snow as “snow water equivalency.” On Monday, Chabot said, the equivalent of an inch of rain fell over most of the mountainous areas and over the Bridger Mountains, in 48 hours the equivalent of nearly three inches of rain fell.

There is little margin for error in avalanche country.

The profile of this season’s lone Montana victim fit exactly with the National Avalanche Center’s description of the “typical avalanche victim in the U.S.” The typical victim is a male, between the ages of 25 and 40, and skilled at his sport. The man who lost his life right before Thanksgiving was Donnie Duane McKay, from North Dakota. McKay, 31, was an experienced operator of snow machines and had been coming to the Cooke City area for eight years.

On Nov. 26, McKay and another rider were riding their snow machines together on the Daisy Pass Road at the base of Henderson Peak. It was near midday when the incident occurred.

An avalanche was likely that day, as the danger level was listed that morning as “high.” The area was hit with a series of storms in the preceding two weeks: Nov. 13-16, eight inches of snow; Nov. 21-22, nine inches of snow; Nov. 23-25, five to six inches of snow; and around Nov. 25-26, more than 24 inches of snow in 36 hours. The snow that fell right before the incident was the equivalent of 2.3 inches of water.

Compounding the weak snow layer topped with wet snow, the wind was blowing steady at 20 mph with gusts up to 40.

High wind, steep slopes and heavy snowfall are a prescription for disaster.

In times of high avalanche danger, one of the keys to safety is to stay on groomed trails and roads. McKay left the road and started up a shallow slope toward a gully “with a large, steep open slope above it…” The avalanche that took McKay’s life was about 300 feet wide and two to three feet deep. It ran for 400 vertical feet. McKay was found lying face up, buried in five feet of snow, 100 feet from the road.

McKay and his riding companion did many things right. They were equipped with the proper safety gear. Both were wearing avalanche airbags, and they had shovels, probes and avalanche transceivers. McKay was wearing a helmet. The likely fatal flaw was their failure to pay attention to the warnings.

Avalanche danger advisories can be found online at www.mtavalanche.com/advisory or http://missoulaavalanche.org/. Daily advisories are also available by phone at 587-6981 or 257-8402.

In the final two months of 2014, the Gallatin National Forest Avalanche Center reported 11 avalanche incidents, including the one fatality:

• On Nov. 20 a skier was caught by a slide in the Bridger Range bowl north of Hardscrabble.

• On the day before McKay’s death, two skiers triggered slides in the northern Bridgers. On Nov. 26, “many skiers triggered slides in the Bridger Bowl.”

• On Nov. 28, two snow machine riders were caught near Cooke City, one rider deployed an airbag and was not buried, the second machine was buried seven feet deep.

• On Dec. 6, a snow machine rider triggered an avalanche at Crown Butte near Cooke City. He was caught but not buried.

• On Dec. 10, a snow machine rider triggered an avalanche at Crown Butte. He was not caught.

• On Dec. 11, a snow machine rider triggered an avalanche at Chimney Rock near Cooke City. He was not caught.

• On Dec. 17, a snow machine rider triggered an avalanche in the Frazier area of the northern Bridgers. He was not caught.

• There were two incidents on Dec. 21 in the north Gallatin. Climbers were nearly hit at Killer Piller in Flanders and two climbers were almost swept off Silken Slot.

When avalanche danger is high, Chabot said, “You can still go out and play, you just have to be diligent. Don’t get on or underneath avalanche terrain. If you’re going to cross country ski, stick to the trail. If you’re going to ride a snowmobile stick to where it’s been groomed.”

Chabot listed off the primary safety precautions for people who want to go into the backcountry for recreation.

• Take an avalanche class. The Gallatin National Forest Avalanche Center offers free courses. For information about the classes go online to www.mtavalanche.com/education/classes/workshops or call 587-6984. At the Avalanche Center website there are also online tutorials. Courses are also available from the Flathead Avalanche Center in Hungry Horse, online at www.flatheadavalanche.org/education or by phone at 387-3835.

• Carry the proper rescue gear, including rescue beacons, probes and shovels.

• Check advisories on the day you plan to go: 587-6981 or 257-8402. “A week ago in some areas it would have been difficult to trigger and avalanche,” Chabot said. Now, just a few days later with the addition of three feet of wet snow, the danger is high.

When Chabot is out in the backcountry he often sees people taking risks. “Whenever we see people skiing in serious avalanche terrain -- big, open, steep slopes -- we’re always biting our fingernails hoping they don’t trigger something,” he said.

Pay attention. “Mother Nature gives you lots of signs of instability,” Chabot said.

Terence Corrigan can be reached at terence.corrigan@helenair.com

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