The current storm could bring another 15 to 20cm of snow by Thursday afternoon. Wind loaded features in the alpine and treeline are the most likely areas for human triggering. large loads, such as cornice failures, could trigger a deeper weak layer.
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain on Thursday
Weather Forecast
Another 15 to 20cm of new snow is possible through the night and into Thursday. Winds will swap from E to N to W and remain light. Temperatures are dropping as are freezing levels. Light flurries are forecast for Friday and Saturday.
Avalanche Summary
Nothing new was observed, but visibility was quite limited.
Snowpack Summary
5cm of new snow has fallen since this morning and it is not yet clear if this is the beginning of the "intense storm" or if the storm has lost some power. Soft slabs continue to form at alpine and treeline elevations and these remain sensitive to triggering in steep, unsupported lee terrain, especially where the slabs sit on buried crusts. The snowpack also continues to settle due to overall warm temperatures. Sun crusts and temperature crusts formed yesterday are now buried under today's snow. Cornices also continue to be a concern as they are large and have become active in recent days.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
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.