23-24

Whumping and Ectp 8 in cook city

Date
Activity
Skiing

Whumping on approach when not is snowmobile tracks. Dug a pit on a north east face slope off the Miller creek road approach to daisy pass at ≈ 9000ft . Shallow snow pack 110cm. Ectp 10 60 cm from ground 26 deg slope. Choose to ski low angle south west facing slope with no terrain above. No recent natural slides were observed. 

Region
Cooke City
Location (from list)
Daisy Pass
Observer Name
Nelson

Tele Meadows

Date
Activity
Snowboarding

Great walk, much better travel than other areas. Started noticing cracking, collapsing, and whumfing around 7800' on east facing slopes. ECTP 11 on our stability test. Much better snow than bacon rind and other similar areas.

Region
Southern Madison
Location (from list)
Telemark Meadows
Observer Name
Nelson VanTassel

Surface hoar observed at the top of Bradley Meadows

Date
Activity
Skiing

Well developed (2-3mm) surface hoar observed at the S shoulder of Bradley Meadows (at the top of the skin track). Some of the crystals had already been blown over, but most were still upright.  

Region
Bridger Range
Location (from list)
Bradley Meadow
Observer Name
Dan Sandberg

Whumpf-ing at Telemark Meadows

Date
Activity
Skiing

Heard two large whumpfs when heading up the low angle slopes of Telemark Meadows. Dug a quick pit and found it was collapsing 30cm (rough estimate) deep on the second weak layer from the top. Lightly snowing, not much accumulation.

Region
Southern Madison
Location (from list)
Telemark Meadows

ECT Test- Poor Test Scores- Instability

Date
Activity
Snowmobiling

Conduction ECT test. 
Observed two well preserved layer of surface hoar
1st layer- 45 cm below surface. 3cm thick layer of surface hoar.

Region
Island Park
Location (from list)
Two Top
Observer Name
Dru Zolman- Ride Rasmussen Style A1 Course

Blackmore

Date
Activity
Skiing

Went for a tour up to Blackmore today. We observed a few natural slides that released in the past few days. Most had relatively small crowns being 1foot, with crowns around 50 foot and ran short distances. We observed a rather large crown near the Blackmore summer trail just below the saddle that also released naturally and looked to have up to a 4 foot crown.

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Tommy S

GNFAC Avalanche Forecast for Sat Jan 27, 2024

Snowpack and Avalanche Discussion

<p><span><span><span><span><span><span>Avalanche conditions are dangerous and a person can easily trigger avalanches on steep slopes. In the southern parts of our forecast area snowfall has been minimal for a few days, and in the Bridger Range nearly a week has passed without snow. Despite a lack of new snow to load the snowpack we continue to hear of recent avalanches and signs of instability. This shows a widespread unstable snowpack and the high potential to trigger an avalanche on any steep slope.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Yesterday we rode around Lionhead Ridge and saw dozens of avalanches that occurred on all aspects and elevations at various times over the last week, some as recent as Thursday (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30278"><span><span><span><strong><span… and observation</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=LKXiHCgovsk&amp;list=PLXu5151nmAvSH326z…;). Also yesterday, Big Sky ski patrol triggered a very large avalanche on the North Summit Snowfield (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30303"><span><span><span><strong><span…;), and Bridger Ski Patrol triggered a couple 12-18” deep slabs, all with explosive mitigation in areas that have been closed so far this season.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>We have had reports of avalanches and collapsing and cracking every day for the last three weeks (see the </span></span></span></span></span></span><a href="https://www.mtavalanche.com/weather/wx-avalanche-log"><span><span><span… and avalanche log</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span> for the full list). Some notable recent activity includes:</span></span></span></span></span></span></p>

<ul>
<li><span><span><span><span><span><span>A slide likely triggered by a skier low on Saddle Peak on Thursday (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30261"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Apparently natural, large avalanches near Cooke City that likely broke on Thursday (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30282"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>A large slide on Buck Ridge that appeared to have happened Thursday (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30299"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Riders in Tepee Basin had cracks shoot 100 ft in front of them while sidehilling a low angled slope (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30269"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Skiers remotely triggered avalanches multiple days in a row near Cooke City (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30267"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
</ul>

<p><span><span><span><span><span><span>Avalanches have been triggered from hundreds of feet away (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30257"><span><span><span><strong><span… Creek remote trigger</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30196"><span><span><span><strong><span… Ridge avalanche</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>) which means you need to be cautious traveling near and underneath steep slopes. Carefully choose your route of travel. Find slopes less than 30 degrees steep which are not directly below or connected to anything steeper (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=_d5_vlY-bjg&amp;list=PLXu5151nmAvSH326z… about terrain assessment</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Human triggered avalanches are likely and the avalanche danger is CONSIDERABLE.</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.

BBSP explosive triggered slides

Bridger Bowl
Bridger Range
Code
SS-AEc-R2-D2-O
Elevation
8500
Aspect
E
Latitude
45.81560
Longitude
-110.92300
Notes

From email 1/26/24: "7 ANFO jug shots were used in D-Rt and S-1. [Areas not open to public skiing yet this season]

Joel's Belly which broke 12-18" deep 50+' wide on the wind loaded south shoulder above the joel's zip drive - majority of the debris didn't go too far, southside portion rolled off the stubborn angle and down onto the z-fan.

Z-Chute southside above traverse to lost shot bowl removed the seasons snowpack down to the basal crust. 50-100 ft wide, pulling the faceted snow off the steep rocky wall to the south and put a lot of debris on the Z-Fan and ran 100ft below the south bowl traverse.

Middle of Lost Shot bowl released but not very big."

 

Number of slides
3
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
An explosive thrown or placed on or under the snow surface by hand
Trigger Modifier
c-A controlled or intentional release by the indicated trigger
R size
2
D size
2
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year