19-20

On 2/9/20 we saw deep avalanche crowns throughout the Bridger Range. These broke at various times throughout the recent storm that deposited 4 feet of snow with over 4" of SWE in the last week. This photo shows debris from avalanches that broke across the entire drainage of Truman Gulch. Photo: GNFAC

Bridger Range, 2020-02-09

On 2/9/20 we saw deep avalanche crowns throughout the Bridger Range. These broke at various times throughout the recent storm that deposited 4 feet of snow with over 4" of SWE in the last week. This photo shows crowns from avalanches that broke across the entire drainage of Truman Gulch. Photo: GNFAC

Bridger Range, 2020-02-09

On 2/9/20 we saw deep avalanche crowns throughout the Bridger Range. These broke at various times throughout the recent storm that deposited 4 feet of snow with over 4" of SWE in the last week. This photo shows debris from avalanches that broke across the entire drainage of Truman Gulch. Photo: GNFAC

Bridger Range, 2020-02-09

Today we went hunting for avalanche crowns in the Bridger Range and found some big ones. Avalanches broke deep across most slopes along the entire east and west sides of the range. Some of the most impressive were in Truman Gulch. Stay alert for the possibility to trigger these big slides. Keep the smooth bed surfaces in mind as potential future weak layer when they get reloaded. Photo: GNFAC

Bridger Range, 2020-02-09

On 2/9/20 we saw deep avalanche crowns on all aspects through the Bridger Range. These broke at various times throughout the recent storm that deposited 4 feet of snow with over 4.5" of SWE in the last week. This slide is on a southeast aspect of Bridger Peak around 9,000'. Photo: R. Griffen

Bridger Range, 2020-02-09

On 2/9/20 We saw deep avalanche crowns on the west side of the Bridger Range in almost every drainage from Saddle Peak to Ross Peak. These broke at various times throughout the recent storm that deposited 4 feet of snow with over 4" of SWE in the last week. Photo: S. Cottom

Bridger Range, 2020-02-09

GNFAC Avalanche Forecast for Sun Feb 9, 2020

Snowpack and Avalanche Discussion

<p>During the last three days of high avalanche danger there were 12 reported natural and human triggered avalanches, and 29 reported since the start of February (<strong><a href="https://www.mtavalanche.com/avalanche-activity">avalanche log</a></strong>). Recent avalanches broke up to 3 feet deep within snow from the last four days (<strong><a href="https://www.mtavalanche.com/node/21917">photos</a></strong&gt;, <strong><a href="https://www.mtavalanche.com/node/21907">photos</a></strong&gt;), and some broke over 8 feet deep on weak layers at the base of the snowpack. Either way, avalanches ran long distances and snapped trees. Yesterday I went to the crown of a 4-8’ deep avalanche on Saddle Peak that broke naturally at the start of the storm (<strong><a href="https://www.youtube.com/watch?v=tJUrhcTRHac&amp;list=PLXu5151nmAvSbcbVf…;, <strong><a href="https://www.mtavalanche.com/images/20/natural-saddle-peak-deep-slab-2">…;). Another deep slab was seen near Buck Ridge that ran naturally during the storm (<strong><a href="https://www.mtavalanche.com/node/21931">details and photos</a></strong>). Today similar avalanches can be triggered or break naturally, and are likely on wind loaded slopes.</p>

<p>Yesterday snowmobilers triggered deep storm snow avalanches near Buck Ridge (<strong><a href="https://www.mtavalanche.com/images/20/snowmobile-triggered-avalanche-mc…;), and on road cuts near Portal Creek (<strong><a href="https://www.mtavalanche.com/node/21955">photos</a></strong&gt;). On a road cut near a parking lot a child triggered an avalanche which was small, but potentially deadly (<strong><a href="https://www.mtavalanche.com/images/20/child-triggered-small-avalanche">…;). Avoid small steep slopes that are often not considered hazardous. The recent snow is heavy and unstable, and small avalanches can pile up deep on a road cut or small gully.</p>

<p>Since Wednesday morning the Bridger Range, Hyalite and Big Sky got 3-4 feet of snow equal to 2.5-3.5” of <a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/or/snow/?cid=nrcs142p2… water equivalent</a> (SWE). This was the biggest storm so far this season and it pushed the snowpack to a breaking point. Wind drifted this snow into fresh slabs that can be triggered and add weight to deep weak layers. Today avalanches are likely, especially on wind loaded slopes. Avalanche danger is HIGH on wind loaded slopes and CONSIDERABLE on non-wind loaded slopes.</p>

<p>Since Wednesday the mountains near West Yellowstone and Cooke City got 2 feet of snow equal to 1.5-2” of SWE. Moderate west-northwest wind drifted this snow into fresh thick slabs which are easy to trigger, and could break deeper avalanches on weak sugary snow near the ground (<strong><a href="https://www.mtavalanche.com/node/21852">photo</a></strong&gt;). On any given slope, there will be minimal&nbsp;evidence whether a deep sugary weak layer is unstable or not. Avoid avalanche terrain while these weak layers adjust to the recent storm.</p>

<p>Today,&nbsp;sunny skies will increase the temptation of fresh powder. Stay safe and enjoy the snow on low angle terrain, away from steep slopes above. Human triggered avalanches are likely and avalanche danger is CONSIDERABLE.</p>

<p>If you get out, please send us your observations no matter how brief. You can fill out an&nbsp;<u><strong><a href="https://www.mtavalanche.com/node/add/snow_observation">observation form</a></strong></u>, email us (<u><strong><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></strong></u&gt;), leave a VM at 406-587-6984, or Instagram (#gnfacobs).</p>

Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out and plan to attend one or two: Events and Education Calendar.

COOKE CITY

Every Friday and Saturday, Snowpack Update and Rescue Training. Friday, 6:30-7:30 p.m. at the Soda Butte Lodge. Saturday anytime between 10-2 @ Round Lake.

BOZEMAN