24-25
GNFAC Avalanche Forecast for Wed Apr 2, 2025
<p><span><span><span><strong><span><span>Avalanche Activity:</span></span></strong></span></span></span><span><span><span><span><span><span> Yesterday ski patrols easily triggered soft slab avalanches with ski cuts and explosives. In the Bridger Range where the most snow fell, those slides were much larger and ran surprising distances. Some of these slides broke at the new/old snow interface while others broke on soft layers within the new snow as Dave and Haylee found in the </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34814"><span><span><span><span><span><… Bridgers yesterday</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>. A skier </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34816"><span><span><span><span><span><… Cooke City intentionally triggered a soft slab</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span> on a steep north facing slope.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>There are three avalanche problems to consider today:</span></span></span></span></span></span></p>
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<li><span><span><span><strong><span><span>Wind slabs</span></span></strong></span></span></span><span><span><span><span><span><span> - The strongest winds happened yesterday morning. Fortunately winds overall have been pretty light. Along upper ridgelines and under cornices, light drifting has created pockets of thick new snow and soft wind slabs. These places will be the most likely spots to trigger an avalanche today, but they are also easy to avoid.</span></span></span></span></span></span></li>
<li><span><span><span><strong><span><span>Storm slabs</span></span></strong></span></span></span><span><span><span><span><span><span> - Since yesterday subtle layers in the new snow have been bonding to each other and to the old snow surface, thus reducing the odds of triggering a soft storm slab avalanche, but we can’t write this problem off just yet. </span></span></span></span></span></span></li>
<li><span><span><span><strong><span><span>Dry loose avalanches or sluffs</span></span></strong></span></span></span><span><span><span><span><span><span> - More snow falling today means there will be some sluffing in the steepest terrain. These types of avalanches typically start at your feet and are mostly a concern for skiers or snowboarders. Making a turn or two and stopping to let the sluff run ahead is one option. Read more </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/#dry-loose"><span><span><s…;
</ol>
<p><span><span><span><strong><span><span>Travel advice for today:</span></span></strong></span></span></span><span><span><span><span><span><span> </span></span></span></span></span></span><span><span><span><strong><span><span>(1)</span></span></strong></span></span></span><span><span><span><span><span><span> Avoid places at the tops or sides of slopes where winds have drifted some snow making the powder more cohesive and more likely to avalanche. </span></span></span></span></span></span><span><span><span><strong><span><span>(2)</span></span></strong></span></span></span><span><span><span><span><span><span> Watch for any signs like shooting cracks that the new snow is unstable and consider doing some quick tests like Dave shows </span></span></span></span></span></span><a href="https://youtu.be/FxgIax46oPc?feature=shared"><span><span><span><span><s… this video</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>. Jump on </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/#test-slope"><span><span><… test slopes</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span> and walk/ride above other tracks to get a feel for how the new snow is bonded. </span></span></span></span></span></span><span><span><span><strong><span><span>(3)</span></span></strong></span></span></span><span><span><span><span><span><span> If getting into steeper terrain where getting pushed downhill could be a problem, consider </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/#dry-loose"><span><span><s… to manage sluffing</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Today the avalanche danger is MODERATE.</span></span></span></span></span></span></p>
Storm/Wind Slab N aspect 9600', Cooke City
From email: "Ski touring near Cooke City today we intentionally triggered a storm slab/ wind slab on a steep north aspect around 9600'. It was about 6" deep, and 30' wide." Photo: B Fredlund
Forecast link: GNFAC Avalanche Forecast for Wed Apr 2, 2025
Well bonded new snow
We skinned up to the Beehive-Bear ridgeline, down into Middle Basin, up Middle Peak and returned the way we came.
It snowed on and off all day, with little accumulation and patches of sunshine mixed in. Winds were moderate at ridgelines and light-calm lower down. During the periods of sunshine we had good views into Beehive and middle basin. We saw no recent avalanches or signs of instability.
There were 10-12" of new snow from the last couple days above firm crusts. The new snow had bonded well to the crust. We encountered a little wind drifting at the ridgeline, but it hadn't formed much of a windslab. Loose dry sluffs were the biggest hazard we encountered. The little bit of sunshine densified the snow surface and caused roller balls, but wasn't enough to increase the hazard.
In one steeper roll over, I got shooting cracks and a small storm slab to break at my ski tips. Photo: GNFAC
testing
testing
Storm Snow in the Bridgers
We headed out to the Bridgers this morning with 13" (1.4" SWE) and more on the way. It may have been April Fool's Day but this was no joke - it is deep out there! We rode out to the Throne and made our way up the East Ridge. On top of the foot of fresh, it snowed around 3-5" in the three hours we were out there.
Our main concerns today were dry loose, storm slab, and wind slab avalanches. We were able to trigger small, loose snow avalanches on steeper slopes in the upper 6" of snow. In one steeper roll over, I got shooting cracks and a small storm slab to break at my ski tips. We did not see other cracking in the recent snow. Visibility was very limited, but we saw one small, filled-in crown near steep, rocky terrain just above the top of the Throne. Winds were blowing all day but were not noticeably drifting snow at mid-elevations.
When we dug down and performed quick stability tests, we got a mix of ECTNs and propagation (ECTP 10, 11) on a hardness change within the storm snow about 12" deep. We noted this hardness change throughout the day. At lower elevations it was only 3-4" deep, while at upper elevations, closer to a foot.
Lower down on the E Face, we saw a glide crack that had opened likely after the warm temperatures from last week.