Avalanche Forecast
Regions: Glacier.
Get up and complete your mission early before the heat of the day destabilizes the snowpack.
The sun keeps getting stronger as we creep towards summer. It can rapidly turn a solid crust into moist mush in less than an hour!
High elevation, N-facing slopes hold dry snow and a "sneaky" surface hoar problem. Watch for slabs up there.
Confidence
High
Avalanche Summary
On Apr 14, a party up Loop Brook saw several sz 2 wet/loose avalanches from steep, S-facing terrain on Mt Green, while a field team on the Youngs traverse saw no natural activity.
On Friday, a skier triggered a sz 2 wind slab on the Dome glacier at 2450 m on a NE aspect. This avalanche likely failed on a layer of surface hoar down 15-40 cm
A wide-propagating(~500m) sz 2.5 was also triggered by skiers Friday on the Bruins Glacier, heading towards the col between Ursus Major and Pk 8812.
Snowpack Summary
Daily melt/freeze cycles are affecting the surface of the snowpack on solar slopes and all aspects BTL, with several crusts of variable strength in the upper snowpack. High alpine, north facing slopes still hold dry snow. A buried surface hoar layer exists down 15-40cm in sheltered north alpine areas above ~2300m. This layer is reactive to human triggering.
Below treeline, conditions are variable and challenging travel exists.
Weather Summary
Sun, gusty winds, and warm by Fri, then a series of storms starting Sat
Tonight Clearing. Alp low -7°C. Ridge wind NW 20-40km/h. Freezing Level (FZL) 900m
Wed Mix sun & cloud. Alp high -4°C. Wind N 25-45km/h. FZL 1800m
Thurs Sun. Alp high -3°C. Ridge wind N 15-40km/h. FZL 1900m
Fri Sun & cloud. Alp high 1°C. Ridge wind W 10km/h. FZL 2200m
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
Avalanche Problems
Wind Slabs
Strong winds late last week formed wind slabs on lee slopes in the alpine. This layer is sitting on a crust and it's able to pick up mass in steep terrain. On high alpine North facing slopes, this wind slab sits on a layer of surface hoar and is producing skier triggered size 2-2.5 avalanches.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2
Loose Wet
Intense spring sun will weaken the upper snowpack, especially on steep solar slopes. Rider triggering is also possible. Use caution in steep terrain and around terrain traps.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 2