Avalanche Forecast
Issued: Dec 30th, 2016 4:14PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
jlammers,
Avalanche Canada
The winds will likely drive the avalanche danger over the next day or so. If you see loose snow drifting or getting blown off ridgecrests, expect an increase in wind slab activity.
Summary
Confidence
Moderate - Wind effect is extremely variable
Weather Forecast
Saturday: Mix of sun and cloud with 3-8cm of new snow expected on Saturday night / Moderate westerly winds / Alpine temperatures of -13Sunday: Mix of sun and cloud with light flurries / Moderate northeast winds / Alpine temperatures of -18Monday: Mix of sun and cloud / Strong northeast winds / Alpine temperatures of -20
Avalanche Summary
On Thursday several size 1-1.5 avalanches could be easily ski cut behind ridgecrests on all aspects in the new snow. A few days ago, a large human-triggered avalanche was reported near Corbin in the Flathead Range in an area where wind had firmed up the surface snow and where sugary facets were present lower down in the snowpack. There's lots of loose snow available for redistribution, so if the wind picks up, expect an increase in wind slab avalanche activity.
Snowpack Summary
Up to 50 cm of low density snow has recently fallen, which is now available to be redistributed by mostly moderate westerly winds. The new snow sits above a variety of surfaces including old hard wind slabs and surface hoar. The cold weather in early December left several layers of weak surface hoar and facets which are now buried 50-80 cm deep. These layers are expected to be more in reactive in areas where the overlying slab has gained cohesion with wind or settlement. A thick crust rain crust from mid-November is near the bottom of the snowpack and remains well bonded to the surrounding snow.
Problems
Wind Slabs
Expect fresh wind slabs to form at higher elevations especially if the winds pick up and redistribute loose snow. In shallow snowpack areas, these slabs could pull out to deeper layers below, increasing the severity of an avalanche.
In shallow areas, be aware of the potential for avalanches to step down to deeper snowpack layers.Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 31st, 2016 2:00PM
