18-19

GNFAC Avalanche Forecast for Wed Jan 16, 2019

Snowpack and Avalanche Discussion

<p>When the snowpack talks, we need to listen. On Sunday and Monday there were two triggered avalanches in the Taylor Fork area of the southern Madison Range. One was skier triggered (<strong><a href="https://www.mtavalanche.com/images/19/skier-triggered-near-taylor-fork"…;, <strong><a href="https://www.mtavalanche.com/node/19716">details</a></strong&gt;) and another was triggered by a snowmobiler on Skyline Ridge (<strong><a href="https://www.mtavalanche.com/images/19/snomobiler-triggered-skyline">pho…;, <strong><a href="https://www.mtavalanche.com/node/19715">details</a></strong&gt;). Both were 2-3 feet deep and ran on weak facets at the ground and either could have been deadly. It has been 8 days since the last snowfall, yet avalanches are still being triggered. The snow structure is bad. Traveling off a beaten path means you’ll wallow in the unsupportable facets. I rode into Taylor Fork yesterday and no matter how many snowpits I dig this season, I’m always surprised at how weak the snow is (<strong><a href="https://www.youtube.com/watch?v=3Y_F3uaJKvI&amp;t=0s&amp;list=PLXu5151n…;). Taylor Fork, <a href="https://www.youtube.com/watch?v=BQ6V8-Pdb3M&amp;t=0s&amp;list=PLXu5151n… Creek</a>, <a href="https://www.youtube.com/watch?v=b3LBdamYYvU&amp;t=0s&amp;list=PLXu5151n…;, <a href="https://www.mtavalanche.com/node/19658">Bacon Rind</a>…they are all similarly shallow and weak. If Mother Nature talks (collapsing, cracking, avalanches), you should be a good boy and girl and listen to her advice to stay out of avalanche terrain. For today, since triggering avalanches is still possible, the avalanche danger is rated MODERATE on all slopes.</p>

<p>Triggering an avalanche in the northern mountains and around Cooke City is unlikely, but not impossible. It’s been a depressingly dry January (<strong><a href="https://www.mtavalanche.com/images/19/snowpack-graph-snotel-gnfac-area-…;) and without a new snow load it becomes more difficult to trigger slides. However, it would be imprudent to think all avalanche terrain is safe. A sledder triggered a small slide in Buck Ridge on Friday which Ian and Alex investigated (<strong><a href="https://www.mtavalanche.com/images/19/snowmobile-triggered-avalanche-mc…;, <strong><a href="https://www.youtube.com/watch?v=VnA2ZhT8vzY&amp;t=0s&amp;list=PLXu5151n…;), and Eric had collapsing and cracking on Saturday north of Big Sky (<strong><a href="https://www.youtube.com/watch?v=Ryd8fZKwVmo&amp;t=0s&amp;list=PLXu5151n…;). Sugary facets at the ground make for a poor and weak snow structure. These isolated signs of instability illustrate the lingering potential to trigger a slide. Anytime we find a dense slab of snow capping soft, airy facets, we take notice. A crack or collapse should be enough to turn us around. For today, the avalanche danger is rated LOW. It’s not a “turn your brain off” low, but a “pay attention” low.</p>

<p>If you get out and have any avalanche or snowpack observations to share, contact us via our <u><a href="https://www.mtavalanche.com/node/add/snow_observation">website</a></u&gt;, email (<u><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></u&gt;), phone (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: Events and Education Calendar.

BOZEMAN

January 16, 17 and 19 or 20, Intro to Avalanches w/ Field Day, Info and Register Here.

Skier Triggered avalanche near Taylor Fork

Taylor Fork
Southern Madison
Code
HS-ASu-R3-D2.5-O
Elevation
10000
Aspect
NE
Notes

From an email:

"We remote triggered this deep slab on our ascent. 10000 feet on ne aspect, slope around 40 degrees. Recently loaded and failed on advanced facets above an October ice crust. In places pulled the crust to the ground. As-hs-r3-d2.5 plus. Crown 2-3 feet flanks 400 ft. Spooky settlement."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
3
D size
2.5
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
30.0 inches
Weak Layer Grain type
Faceted Crystals
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Snowmobiler triggered on Skyline Ridge

Skyline Ridge
Southern Madison
Code
HS-AMu-R2-D2.5
Elevation
10000
Aspect
SE
Latitude
44.91620
Longitude
-111.22000
Notes

From an email:

" There was a avalanche on Sunday in Cabin Creek, it appears that a few rider's were high marking an open face, didn't see it happen but I did observe rider's from a distance in that area."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
2
D size
2.5
Problem Type
Wind-Drifted Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skiers triggered this large slide as they ascended (2-3 feet deep x 400 feet wide). It broke on a NE aspect at 10,000 feet on a 40 degree slope. It was recently wind-loaded and failed on facets at the ground. This occurred on Monday, January 14. Photo: Anon

Southern Madison, 2019-01-16