Snowpack and Avalanche Discussion
<p><span><span><span><span><span><span>In the Bridger Range, 20” of new snow (1.2” snow water equivalent (SWE)) and increasing west wind creates very dangerous avalanche conditions on wind-loaded slopes. Human-triggered and natural avalanches are likely, especially where the new snow is drifted into thicker slabs. Avalanches of new and wind-drifted snow will be large enough to bury a person, and there is a chance larger avalanches will break deeper on older buried weak layers. Avoid travel on and underneath steep, wind-loaded slopes. Conservative decision making and cautious route finding are essential today. With wind expected to increase and a few more inches of snow, stability will get worse. Avalanche danger is HIGH on wind-loaded slopes and CONSIDERABLE otherwise.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>In the northern Gallatin Range, moderate to strong wind will drift 8” of new snow (0.6” SWE) into denser, thick wind slabs that are easy for a person to trigger. On wind-loaded slopes, human triggered avalanches are likely and could be large enough to bury or injure a person. On non-wind loaded slopes avalanches could break below the new snow, possibly on weak layers buried 2-3 feet deep. Be extra cautious of wind-loaded slopes, and carefully assess the stability of new snow and buried weak layers before riding or crossing any steep slope. Avalanche danger is CONSIDERABLE on wind-loaded slopes and MODERATE on non-wind loaded slopes.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>In the Madison Range and southern Gallatin Range 5-10” of low-density snow (0.2-0.4” SWE) creates heightened avalanche conditions. A person can trigger a slab of freshly drifted snow which may be large enough to bury you, but even a small drift can be dangerous if it carries you into a terrain trap like trees or over a cliff. The weight of fresh drifts may cause avalanches to break deeper and wider on weak layers buried 1-3 feet deep. Before riding steep slopes, carefully evaluate the snowpack for fresh drifts and buried weak layers. Avalanche danger is MODERATE.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Near Cooke City and West Yellowstone, a person can trigger avalanches that break in recently formed drifts of snow, or fresh drifts that form as snow falls later today (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/snowmobiler-triggered-avalanche-l…;). Recent wind out of the north and west drifted snow into thicker slabs, and two days ago, riders north of Cooke City saw a recent snowmobile triggered slide on Crown Butte (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/28183"><span><span><span><strong><span…;). Today, new snow will be drifted into fresh slabs that can be triggered by a skier or rider. Before riding steep slopes, carefully evaluate the stability of recently formed drifts. Avalanches on weak layers buried 1-3 feet are currently unlikely, but it is worthwhile to dig to assess these weak layers before riding steep slopes (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=fxaqxUH9umA"><span><span><span><strong>… video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Avalanche danger is MODERATE on wind-loaded slopes and LOW on non-wind loaded slopes.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Expect avalanche danger to rise overnight and tomorrow. If heavy snowfall begins early today, fresh unstable drifts may form and cause danger to increase by this evening.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Please share avalanche, snowpack or weather observations via our</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/add/snow_obs"><span><span><span><span>…; </span></span></span></span></span></span><span><span><span><strong><span><u><span><span>website</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, email (</span></span></span></span></span></span><span><span><span><strong><span><span>mtavalanche@gmail.com</span></span></strong></span></span></span><span><span><span><span><span><span>), phone (406-587-6984), or Instagram (#gnfacobs).</span></span></span></span></span></span></p>
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.