Deadly avalanche season: The risks are growing

From Mount Rainier to Mount Baker, the lure of unusually heavy and persistent snow has drawn many to the state's pristine backcountry areas.

But those conditions have resulted in the state's deadliest avalanche season in 30 years — and there are nearly five more months left in the season.

Eight people have been killed or are presumed dead as a result of avalanches in Washington state since Dec. 1. Most recently, two people were killed Tuesday when an avalanche hit a group of snowmobilers north of Mount Baker.

Weather forecasters warn more snowfall across the Cascades and Olympics as well as Mount Hood, in Oregon, could bring dangerous avalanche conditions this weekend.

Paul Baugher, director of the Northwest Avalanche Institute, attributes the high number of deaths to unusual weather conditions, the increase in the popularity of the state's backcountry areas and to visitors' lack of preparedness for dealing with avalanche danger.

"No other type of risk is as alluring and seductive," said Baugher, who is also chief of ski-patrol operations at Crystal Mountain ski area, near where three snowboarders are believed to have died in avalanches Dec. 1 and Dec. 2.

Heavy snowfall has accumulated quickly in the mountain ranges, creating ideal conditions for ski resorts but also a perilous situation for hikers, skiers, snowboarders and snowmobilers heading to the backcountry. Strong southerly winds and moderate-to-heavy precipitation were expected in the Cascades, Olympics and at Mount Hood Thursday and today. The additional accumulation of snow was expected to add to the danger.

"It's just staying bad. It's not getting any better," said Kenny Kramer, avalanche metrologist with the Northwest Weather and Avalanche Center. "We had several classic scenarios, recipes for bad avalanches."

Avalanche experts said they are seeing a continued theme of snowpack instability this season.

Snow in Washington usually falls wet and heavy, and even a deep snowpack can be solid. But this year is different, Kramer explained.

So far this year, Washington's snowpack is 30 percent to 60 percent above normal, and the snow isn't falling in the usual steady pattern that leaves a hard, solid snowpack, Kramer said. The conditions are similar to those in previous La Niña years, when avalanche deaths also increased, but not to this season's level.

The La Niña weather system causes cooler ocean temperatures, and leads to drier weather in the Southern Hemisphere and wetter-than-normal winters with more rain and snow in the Pacific Northwest.

In early December, a storm dropped more than 20 inches of snow in the mountains over an 18-hour period, immediately followed by warmer weather and rain. The same storm system that brought record floods to Western Washington's lowlands brought a high avalanche danger to the mountains, Kramer said.

After the rain in early December, the snowpack refroze into a smooth, solid layer. When light, fluffy snow fell onto the hard crust, it created a new and different avalanche danger that led to the death of a snowshoer on Dec. 18 in Mount Rainier National Park.

Then a third kind of avalanche danger developed when dense snow fell on top of the existing powder and the wind picked up, creating new peaks of dangerous snow that led to the snowmobiler deaths this week, Kramer said. Baugher likened to effect to parking "an Oldsmobile on a bag of potato chips."

Baugher said crews at Crystal Mountain are doing avalanche control almost seven days a week to make sure the resort's inbounds ski areas aren't struck by sliding snow.

"We just haven't had many breaks [in the weather]," he said. "It has been an onslaught; the patrollers are tired."

On average, the Pacific Northwest sees one or possibly two avalanche deaths during the November-to-May avalanche season, Baugher said. Of the 13 avalanche deaths nationwide this season, eight were in Washington. The others were in Utah (three), and Colorado and Wyoming (one each).

Between 1995 and 2005, 24 people died because of avalanches in Washington state, according to the King County Office of Emergency Management.

Baugher said people who venture to ski resorts but leave the designated ski area increase their avalanche risk tenfold.

At Mount Rainier National Park, where backcountry enthusiasts are encouraged, visitors are advised that the avalanche danger is high and to enjoy the snow at their own risk, park spokesman Kevin Bacher said.

"If the danger is high, people should stay out of the areas that are prone to avalanche," Bacher said. "We have always recommended that people stop in at the visitors' center or call us before heading out."

Baugher believes most of the people killed this season were aware of the avalanche danger but ignored the warnings. He said that many of the people probably hadn't had formal avalanche training.

"In the Northwest, people are used to skiing in storms. But in the past they've been lucky because what they didn't know didn't hurt them," he said. "Now what they don't know is killing them. There's no substitute for the training."

International Mountain Guides, based out of Ashford, near Mount Rainier, and The Mountaineers, based in Seattle, both offer avalanche training courses. Baugher, who teaches the courses for International Mountain Guides, said they teach participants how to assess the hazards and travel safely in potential avalanche areas.

Kramer, from the Northwest Weather and Avalanche Center, adds that the snow-sports conditions are great and people can still have fun while staying safe. He advises staying closer to the trees and away from higher, more windy terrain.

"You don't want to go out there if you don't know what you are doing or [don't] have the proper equipment," Kramer said. "Have some training and some savvy."

Information from The Associated Press is included in this report.

Jennifer Sullivan: 206-464-8294

or jensullivan@seattletimes.com