On January 18, 2022 a weak layer of surface hoar was buried by 1-2" of new snow near Cooke City. As more snow builds a slab over this weak layer it will cause avalanches. Photo: GNFAC
21-22
On January 18, 2022 a weak layer of surface hoar was buried by 1-2" of new snow near Cooke City. As more snow builds a slab over this weak layer it will cause avalanches. Photo: GNFAC
East Face Argentina Bowl
Date
Activity
Skiing
Skied the center of the east face in Argentina bowl. The snow on the steeps was full depth facets and we were skimming rocks in our turns and creating small sluffs. No slab present. The conditions quickly transitioned to a more consolidated snowpack as the slope angle decreased. We did not dig on this aspect but were able to ski cut the top of the bowl with no results before skiing.
Region
Bridger Range
Location (from list)
Argentina Bowl
Observer Name
Zach Tondre
Bacon Rind
Date
Activity
Skiing
Well-developed surface hoar at bacon rind up in the meadows and in the burn.
Region
Southern Madison
Location (from list)
Bacon Rind
Observer Name
Jacob Zimmerer
GNFAC Avalanche Forecast for Tue Jan 18, 2022
Snowpack and Avalanche Discussion
<p>The snowpack across the advisory area is generally stable and the expected snow won’t be enough weight to change this. However, don’t mistake today’s overall stability to mean an absence of weak layers. Riders and skiers have spotted a feathery layer of weak surface hoar growing from West Yellowstone to Cooke City. When it gets buried today, this will be our new layer of concern until proven otherwise (<a href="https://mtavalanche.com/images/22/surface-hoar-near-cooke-city"><strong… photo</strong></a><strong>, </strong><a href="https://mtavalanche.com/images/22/west-yellowstone-surface-hoar"><stron… photo 1</strong></a><strong>, </strong><a href="https://mtavalanche.com/images/22/surface-hoar-formation-lionhead"><str…;). It will not be a significant hazard with the minimal snow arriving today, but it will be as it gets buried deeper. Help us map its extent by <a href="https://mtavalanche.com/node/add/snow_obs"><strong>letting us know</strong></a> if you see it on the surface or see shooting cracks and surprising reactivity in today’s inch or two of new snow.</p>
<p>Without significant new loading, Doug and Alex remind us to focus on the basics during times of low danger by testing the snowpack, assessing for isolated instabilities and employing safe travel practices (<a href="https://www.youtube.com/watch?v=bmstU9sCAmM"><strong>Doug in the Bridger Range</strong></a><strong>, </strong><a href="https://www.youtube.com/watch?v=8gxJKiQe_Jo"><strong>Alex in Cooke City</strong></a>). Groups in the Madison, Northern Gallatin and Bridger Ranges have reported <a href="https://www.youtube.com/watch?v=Gk8W8nlUMpw"><strong>snowpits</strong><… have failed and propagated in isolated areas, indicating a potentially unstable combination of a buried weak layer and an overlying slab of snow (<a href="https://mtavalanche.com/images/22/ernest-miller-ridge"><strong>photo</s…;). These groups (and all the ones who are reporting stable test results) are nailing it! They know that even though avalanches are generally unlikely, they need to test stability to make a slope-specific forecast before skiing or riding. If they identify areas of isolated instability, they go somewhere else. Keep it up.</p>
<p>Today, human-triggered avalanches are unlikely to break deeper than the 1-2” of new snow that falls during the day, and the danger is LOW. </p>
<p>If you get out, please send us your observations no matter how brief. You can submit them via our <a href="https://www.mtavalanche.com/node/add/snow_observation"><strong>website<…;, email (<a href="mailto:mtavalanche@gmail.com"><strong>mtavalanche@gmail.com</strong></a…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>
Upcoming Education Opportunities
The West Yellowstone Beacon Park is up and running! Stop by to check it out and practice with your rescue gear.
See our education calendar for an up-to-date list of all local classes. Here are a few select upcoming events and opportunities to check out:
Weather and Avalanche Log for Tue Jan 18, 2022
Buried SH @ S Madison, S. Gallatin, Lionhead, Cooke
Mt. Blackmore
Date
Activity
Skiing
My group and I decided on Blackmore and left the trailhead around 0930. We saw a few folks on the way out to Blackmore and a couple heading back after an early morning. The weather was really nice the whole way out, unseasonably warm and not very windy at all. The warm weather is a little disappointing overall, but it made for a pleasant skin out to the base of Blackmore. The lookers right shoulder of the mountain was very tracked up and there were scatter tracks throughout the rest of the east face. We went up to 9400' near one of the lower cliff bands to dig a pit and do some stability tests. We ended up digging on a bulls eye east aspect in 110cm of snow. There were a surprising amount of layers in the snow with a soft layer of about 5-10cm of the most recent snow on top of a hard wind packed slab. Under that slab was a layer of softer rounds followed quickly by the 25-45cm of facets separated by some thin crusts. We got a CT12 and ECTP17 Q2 both breaking at the basal facet layers about 35cm from the ground. We opted for the tracked up shoulder, not the best skiing but a good day out with friends.
Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Sam Roberts
Upper McAtee Basin
Date
Activity
Skiing
Variable conditions observed in upper McAtee Basin yesterday afternoon (1/16). Sastrugi, sun cupping, punch crust, edgeable ice, dry powder, and wet snow all present.
Cheers - Ryan
Region
Northern Gallatin
Location (from list)
McAtee Basin
Observer Name
Ryan Kropp
Maid of the Mist Bowl on Arden Peak/ bowl
Date
Activity
Skiing
We dug a very quick pit at the base of the bowl on the Maid of the Mist side of Arden Peak, and noticed slabs, the first of which was about 6 in down, and the second an additional foot down. Below the second slab was some worrying sugary snow that was sliding the slabs around as we were digging. We did not perform full column or propagation tests, but did decide to turn around early.
Region
Northern Gallatin
Location (from list)
Maid of the Mist
Observer Name
Lura Johnson
Cooke City, Republic Peak
Date
Activity
Skiing
We found well developed surface hoar on all aspects and elevations - up to 10k - except on steep south facing slopes.
Region
Cooke City
Location (from list)
Republic Mountain
Observer Name
Ryan Griffiths