Weather and Avalanche Log for Mon Apr 14, 2025
Temps: Teens to low 20s F; 8 Degrees Lone Mountain Summit
Temps: Teens to low 20s F; 8 Degrees Lone Mountain Summit
I rode the motorized zone and noticed natural wind slab avalanches running pretty far on: East Henderson, SE Scotch Bonnet, East Miller, NE Crown Butte. D1.5-2.0
Loose wet debris from yesterday were also present in many places.
I rode the motorized zone and noticed natural wind slab avalanches running pretty far on: East Henderson, SE Scotch Bonnet, East Miller, NE Crown Butte. D1.5-2.0
Loose wet debris from yesterday were also present in many places.
<p><span><span><span><span><span><span>Wild weather yesterday likely threw down some </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/#graupel-rimed-particles">…; and other variations in the 10” of dense, new snow along with a </span></span></span></span></span></span><a href="https://www.mtavalanche.com/sites/default/files/snow_obs/2025-04/screen… of strong winds</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>. There are two avalanche problems to consider:</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Storm slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> - I’m unsure how well the new snow is bonded to itself and the old snow surface, but it should be dense enough to be a cohesive slab. Assess the stability of the new snow before getting into steep terrain - get onto small steep test slopes, step and ride above your partners tracks, and perform </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/#extended-column-test-ect"… ECT’s</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><strong><span><span>Wind slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> - Strong winds during the storm yesterday drifted the new snow and formed wind slabs that could be two feet thick. Look for places with fresh wind loading and ski or ride around those locations where there’s a good chance you’ll trigger a slide.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Today near Cooke City the avalanche danger is CONSIDERABLE in any wind-loaded terrain with drifting from yesterday’s winds. Slopes untouched by yesterday’s winds have a MODERATE danger.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Cold temperatures have helped refreeze the snowpack ending wet snow problems. With minimal new snow there are minimal dry snow avalanche problems, but still watch out for shallow wind slabs that could sweep you off your feet. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Today the avalanche danger is LOW. For the few hardy folks venturing into out of the way places, watch out for isolated locations that may have received much higher snowfall amounts. Those places will have the danger and avalanche problems more similar to the Cooke City area.</span></span></span></span></span></span></p>
Thunder and Lightning yesterday
Temps well below freezing this morning.
Screenshot of winds from Lulu Pass wind station during the storm.
Screenshot of winds from Lulu Pass wind station during the storm.
Above freezing air temps and cloudy skies
<p><span><span><span><strong><span><span>Wet loose avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> continue to be the main avalanche concern. The snowpack should be mostly wet this morning from above freezing overnight air temperatures and cloudy skies. Wet snow can even be found on north facing slopes except at the highest elevations. Without any sunshine today and cooling temperature this afternoon, I don’t expect much wet snow avalanche activity.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Look out for areas where the snowpack is especially wet and unsupportable like slopes that were in the sun yesterday - wet loose avalanches will be more likely in these areas. Places with more supportable snow will have the lowest likelihood for wet avalanches and better skiing and riding conditions.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Wind slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> were an issue during the past week, but they have likely stabilized. Look out for a few shallow, new ones that may form late today with snow and increased winds.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Large overhanging cornices</span></span></strong></span></span></span><span><span><span><span><span><span> are always a concern, but more so with such warm temperatures. A local guide skiing near Cooke City yesterday </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34899"><span><span><span><span><span><… a large cornice fall midday</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>. Stay far back from the edge of corniced ridges, and move fast if you have to travel under them.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Avalanche conditions are generally safe but the snowpack hasn’t gotten a good refreeze, so the avalanche danger is MODERATE.</span></span></span></span></span></span></p>
Today I was skiing in East Hayden Creek. I witnessed a cornice fall around 1230pm. Also I triggered multiple wet loose avalanches on several aspects including a north facing slope 9400 ft. None bigger than D1