Avalanche Forecast
Issued: Dec 16th, 2019 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
MBender,
Avalanche Canada
Storm snow accumulating over the next few days will gradually increase the load on a buried layer of surface hoar crystals. As a result, expect to see an increase in the likelihood of human triggered avalanches.
Summary
Confidence
Weather Forecast
MONDAY Night: Flurries, accumulation 5-10 cm, moderate west wind, alpine high temperature -9 C.
TUESDAY: Flurries, accumulation 5-10 cm, moderate southwest wind, alpine high temperature -6 C.
WEDNESDAY: Scattered flurries, light to moderate southwest wind, alpine high temperature -7 C.
THURSDAY: Scattered flurries, light to moderate southwest wind, alpine high temperature -8 C.
Avalanche Summary
On Sunday there were several reports of skier triggered size 1 storm slab avalanches up to 30 cm deep on north south and east aspects at treeline.
On Saturday there were two reports of skier triggered persistent slab avalanches size 1-1.5. One was on a south aspect at 2200m and was about 25-45 deep.
Snowpack Summary
25-40 cm of recent snow has accumulated above a widespread layer of large, feathery surface hoar crystals. New snow is expected to continue to accumulate above this layer over the next few days and possibly make it more sensitive to human-triggering.
A weak layer formed in late November is now buried around 1 m below the surface. This is the layer of concern relating to the listed persistent slab avalanche problem. The weak layer may present as surface hoar, a crust, facets or a combination, depending on elevation and aspect. Below this, a variety of crusts from late October are buried deeper in the snowpack.
Problems
Storm Slabs
Storm snow is gradually accumulating on top of a widespread layer of large surface hoar. By Tuesday morning 25-45 cm may be sitting on top of this layer, which may increase the likelihood of triggering.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A combination of crusts from late October is buried 40 to 70 cm deep in the snowpack. This problem will most likely be triggered from shallow areas on steep slopes in the alpine.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 17th, 2019 5:00PM
