Lots of snow rolling, and sliding above wall lake, on this South East face.
Skiers had a collapse which made this crack on a south facing slope with a shallower, wet snowpack around 9,000' near Cooke City.
Skiers had a collapse which made this crack on a south facing slope with a shallower, wet snowpack around 9,000' near Cooke City. Photo: J. Redfield
A wet slab was reported on 4/4/21 around 8,200' elevation in the Main Boulder drainage south of Big Timber, outside of our advisory area. It happened that day or very recently during extended above freezing temperatures.
We saw wet loose avalanches on 4/3/21, on aspects that receive sun and have steep rocky features, likely ran over previous days.
<p>The last four days had temperatures in the 40s and 50s F and the surface of the snowpack barely froze each of the last four nights. The snow will be slow to freeze this morning due to cloudy skies and just barely freezing temperatures. Wet snow avalanches are still a potential hazard, with the addition of avalanches involving new or wind-drifted snow this afternoon depending on how much snow falls.</p>
<p>Decreasing temperatures this morning will help the snowpack freeze and reduce wet snow activity, but some slopes may not freeze or will only have a thin crust before snow or rain falls later today. Avoid travelling on steep slopes where the snow surface is wet and not refrozen. Yesterday we got a report of a natural wet slab in the Main Boulder, outside and adjacent to our advisory area (<strong><a href="https://www.mtavalanche.com/images/21/wet-slab-main-boulder">photo</a><…;). This shows recent warm temperatures have introduced meltwater deeper into the snowpack and made wet slabs possible (<a href="https://www.youtube.com/watch?v=YIajdl9hhyo"><strong>wet slab video</strong></a>). On slopes that do not freeze, the potential for wet slab avalanches will increase if there is rain or heavy snow. The higher you go in elevation, the more likely the snowpack is frozen. Slopes with a thick, supportable crust are generally stable and the main concern will be new snow sliding on these crusts this afternoon if more than a few inches of snow falls, or if it is blown into thick drifts.</p>
<p>See Dave’s <strong><a href="https://www.youtube.com/watch?v=gPpeLRBv-Qo&list=PLXu5151nmAvQDzKmH…; from Beehive yesterday for a discussion on assessing stability during the transition from wet snow to new snow. Today, avalanches are possible and avalanche danger is rated MODERATE.</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>
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:
TONIGHT! April 5, 6:30 p.m., Forecaster Chat with Alex Marienthal, hosted by Uphill Pursuits, “Spring Snowpack and Forecasting Tools”. Link to Join.
Light freeze with temps near freezing and clouds.
This wet slab was reported on 4/4/21 around 8,200' elevation in the Main Boulder drainage south of Big Timber, outside of our advisory area. It happened that day or very recently during extended above freezing temperatures. Photo: G. Smith
Some of the wet loose avalanche activity around Beehive Basin is getting large enough to be dangerous in its own right, other activity is dangerous because it could push us into hazardous terrain.
