Presented at the 2014 ISSW in Banff, Canada.
For the last 24 years, the Gallatin National Forest Avalanche Center has achieved many successes in snowmobile avalanche education but many challenges remain. Building on the efforts of many others and the work outlined by the GNFAC at an ISSW twelve years ago, our snowmobile education has evolved considerably. Live recoveries, unheard of only 10 years ago, seemingly occur every winter now.
Published in Carve, February 2014
I envision that should I ever be buried in an avalanche my partner will locate me quickly, put together his shovel and dig like a maniac. He will be anaerobic, spittle drooling from his mouth, sweat burning his eyes and he’ll be puffing like a locomotive. His heart rate will be in maxxed, his face red and ears ringing. I know this because I carefully chose my backcountry partners. They will give 110% of themselves to save me if I’m buried. They are mentally, emotionally and physically tough.
Mountain snowmobiling is serious business in terms of avalanches. Modern sleds make it incredibly easy to ride deep powder in avalanche terrain. It is really fun but can also be really deadly. As always consider taking a class. Another great way to learn more is to watch a recently published series from the Canadian Avalanche Center (CAC) called "Throttle Decisions." It has 10 individual videos that were all very well done and worth watching.
By Dave Zinn, Forecaster, Gallatin National Forecast Avalanche Center
Digging a Snowpit Matters
An online article posted October 29, 2015 for BackcountryMagazine.com on snowpits, avalanche character, and the difficulties and risks of traveling in various types of snow, is a welcome early season jump-start to get us thinking about snow and avalanches. Every snow climate is different and every professional forecaster looks at the snowpack through his and her own forecasting lens, but we are all trying to increase the understanding of avalanches in order have fun and stay alive.
Published in the Winter 2018 issue of Outside Bozeman
Saddle Peak sits south of Bridger Bowl as a pair of equally high points on the ridgeline. The familiar eastern slope rises 3,500 feet above the highway on the way to Bridger Bowl, and provides an iconic view to those at the ski area. The peak’s extraordinary gullies and faces are the siren’s song to the southwest Montana powder skier.
Published in the Dec 2014 Carve
Put your shovel in the snow!
This simple act could save your life. Pausing to assemble your shovel and dig a few scoops can sometimes reveal a hidden but, once exposed, obvious weak layer. Taking a few more minutes to perform an Extended Column Test (ECT) may give you strong evidence of unstable slopes. When conditions seem good most people have already made their decision to ski or not by the time they reach the top of a slope, but an ECT might change your mind and save your life. Conversely, if you decide to not ski because of dangerous conditions there is no need to dig. Regardless of experience, if we play in avalanche terrain we should hunt for instability.
When venturing into the backcountry, answering these two questions is essential when assessing a slope to ride:
Is the terrain capable of producing an avalanche?
-and-
Can the snow slide?
Avalanches happen when four ingredients are present: a slab, a weak layer, a trigger and a slope steep enough to slide. A key problem when assessing slope angle is that most slopes have varying degrees of steepness. It is critical for riders to assess slope angle frequently.
Winter is in the rearview mirror and spring is gaining momentum but we cannot forget about avalanches. As the seasons change so do the types of avalanches. There are two ways to trigger avalanches: stress the snowpack or weaken it. Dry slab avalanches are common in winter and occur when too much weight (stress) is added to the snowpack. Under a heavy load of new snow, windblown snow or skiers, layers collapse and avalanche from this added stress. In spring the snowpack loses strength and weakens when melting water breaks down snow crystals and provides lubrication between layers. Some types of layers are more prone to this type of weakening and this season the western US has one of the worst: depth hoar.
I would love to know how many sets of tracks were wiped out in Sunday’s avalanche of the Football Field on Saddle Peak. If you carved a set consider yourself lucky. I’m going to guess that not many snowpits were dug and that the only form of stability assessment folks leaned on were that others had skied it beforehand. This was not smart. The avalanche broke during early morning avalanche control on the boundary of Bridger Bowl. An explosive was placed in-bounds, but the avalanche ripped out-of-bounds. Why?
