This forecast is based on very few field observations. This high level of uncertainty warrants conservative terrain selection.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Wednesday evening: 5-15cm of new snow / Moderate southwest winds / Freezing level at 1100mThursday: 8-15cm of new snow / Moderate southwest winds / Freezing level at 1100m Friday: 3-5cm of new snow / Light southerly winds / Freezing level at 1100mSaturday: Mix of sun and cloud / Light southerly winds / Freezing level at 700m
Avalanche Summary
No new avalanches were reported in this region. This may speak to a lack of observations rather than actual conditions. With forecast wind and snow, a natural storm slab avalanche cycle is expected on Wednesday night and into Thursday.We currently have very limited observations from this region. Please submit your observations to the Mountain Information Network (MIN).
Snowpack Summary
Up to 30cm of new snow has fallen in the past few days. At higher elevations, southerly winds (gusting strong at times) likely redistributed the new snow, forming wind slabs on lee features.Below the recent storm snow you may find a couple of crusts which formed during last week's rain. That said, little is known about the reactivity of these crusts or the elevation bands at which you're likely to find them. A major feature in the snowpack is a crust which formed around November 11th and can be found approximately 100cm down at treeline elevations. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 200+cm in the alpine, 100-160cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks.
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.