Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Saturday, March 10 at 7:30 a.m. Pinhead Classic Telemark Festival, in partnership with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
High pressure continues to dominate the weather pattern. At 4 am this morning mountain temperatures are ranging between the high twenties to low thirties in the north and low to mid-twenties in the south. Winds are blowing 10-20 mph out of the WSW and skies are clear. Today, temperatures will warm into the high thirties to low forties in the north and low to mid thirties in the south. Winds will continue to blow 15-25 mph out of the WSW. Warm and dry conditions will prevail through the weekend.
Wet snow avalanche danger
With air temperatures expected to rise well above freezing today, the danger of wet snow avalanches could rise to CONSIDERABLE by this afternoon on sun exposed slopes. The snowpack should give warning signs in the form of pinwheels and point releases. Slopes displaying these signs of instability should be avoided.
The Madison and Gallatin Ranges, the mountains around Cooke City, the Lionhead area near West Yellowstone and the Bridger Range:
Right as winter appeared to be getting a foothold, the all too familiar dry spell has once again elbowed its way back in. We are now entering the fourth day without new snow in southwest Montana, which is not helping powderhounds but is helping the snowpack slowly trend towards stability. As the snowpack adjusts, obvious signs of instability and the potential for triggering an avalanche will gradually decrease. Even though avalanches will become harder to trigger, the presence of persistent weak layers will continue to make human triggered avalanches possible.
Over the past week numerous natural and human triggered avalanches have occurred throughout our advisory area. Yesterday, snow rangers near Cooke City observed multiple slides that took place over the past few days (photo). Also, skiers near Big Sky viewed a large slide on Fan Mountain (photo) and on Thursday skiers near the Yellowstone Club experienced cracking and collapsing and got unstable results during stability test.
Most slides have occurred on slopes that received a heavy wind load earlier in the week (photo); however, some slides have failed on non-wind loaded slopes (video). Our primary concern is a weak, faceted layer buried in mid-February. This layer is now buried 2-4 feet deep and is the culprit for much of the recent activity. Slides that initiate on this layer could potentially step down to faceted layers near the ground. Slopes located in steep rocky terrain or directly below ridgelines will be likely areas to trigger a slide.
The latest round of avalanche activity combined with the presence of buried persistent weak layers continues to highlight the need to objectively evaluate each slope we choose to ride. Digging holes and conducting stability tests such as the ECT are a great way to evaluate the snowpack structure and the relationship between layers.
Today, riding in avalanche terrain will be like approaching a yellow light – You have to observe you surroundings carefully before going for it. If the decision is made to proceed, remember there is always a chance of being unexpectedly broadsided.
Today, heightened avalanche conditions exist on specific terrain features and the avalanche danger is rated MODERATE.
View the definition of MODERATE on the new North American Public Avalanche Danger Scale.
I will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations, drop us a line at mtavalanche@gmail.com or call us at 587-6984.
Events/Education
Come to Bridger Bowl on Saturday, March 17th (St. Patrick’s Day) with telemark skis, AT skis, alpine skis, snowboards, split boards, or even snow blades. The theme is Snowpocalypse based on the wildly popular Mayan 2012 apocalypse. $30 gets you into the races, a pint glass, t-shirt, a good time, a raffle ticket, and food by Cafe Fresco. Pre-register at Mystery Ranch or Grizzly Ridge March 11-16. Visit http://pinheadclassic.com/ or the Pinhead Facebook page for more info.
1-hour Avalanche Awareness at REI, Bozeman
Tuesday, March 20 at 6:30 pm. Sign up for this FREE class here.