Natural avalanches possible, human triggered probable.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural and human triggered avalanches likely.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Regions
Glacier.
Avalanche hazard will rise with the incoming storm. Assess condition continually as you travel today, watching for clues of instability as the snowpack deteriorates.
Weather Forecast
Warm and wet is the forecast for this weekend as intense subtropical moisture hits the region. Expect alpine temperatures around -1, 10-15 cm of snow and light ridge top winds with strong gusts. 15-20 cm of snow is forecast tonight with freezing levels remain high. 10cm of snow is forecast tomorrow with similar temps as today and westerly winds.
Snowpack Summary
Up to 60cm of heavy snow over light snow has created a touchy soft slab. This lies on top of suncrusts on solar aspects, and windslab on N and E aspects. The new slab is failing with easy to moderate results within the new snow, as well as at the old interface. The Jan 28/Feb 10 PWLis down 1.2-1.5m under a cohesive slab.
Avalanche Summary
Several size 2-3 natural avalanches were observed yesterday along the highway corridor. We are expecting a large natural avalanche cycle to occur this weekend with intense precipitation and warm temperatures. Reports indicate that the storm slab is reactive to skier triggering on steep, convex features with remote triggering a possibility.
Confidence
Freezing levels are uncertain
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.