Avalanche Forecast

Issued: Jan 15th, 2018 5:45PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Persistent Slabs and Wind Slabs.

Avalanche Canada simonhorton, Avalanche Canada

It's hard to have confidence traveling in the backcountry right now as sustained warm temperatures stress the snowpack. Very conservative terrain choices are critical!

Summary

Confidence

-

Weather Forecast

TUESDAY: Increasing cloud throughout the day, moderate to strong southwest winds, mild inversion with alpine temperatures hovering around 0 C.WEDNESDAY: Light flurries in the afternoon, strong southwest winds, alpine temperatures around - 2 C.THURSDAY: Light flurries with up to 5 cm of new snow, strong southwest winds, alpine temperatures around -5 C.

Avalanche Summary

Limited reports suggest wet loose avalanches have been running on steep solar aspects. Small thin wind slabs (size 1-1.5) have also been reported.

Snowpack Summary

An unstable weak layer from mid-December (predominantly feathery surface hoar crystals and/or a sun crust) is found at treeline and below treeline elevations. Slabs can fail easily on this layer, either naturally or with the weight of a person or machine. Forecasted warm air temperatures could make this layer even easier to trigger.The snowpack is variable across the region, but persistent slabs are generally a widespread problem. Wind slab and storm slab distribution will be more variable. New wind slabs can be found in parts of the region due to recent southwest winds. Windward alpine slopes may be scoured; and variable wind slabs are found at treeline and alpine elevations. New snow is likely to fail as storm slabs and/or loose avalanches.Deeper in the snowpack, an early-season rain crust and sugary facets exist. An avalanche in motion could step down to these deeper layers, creating a large and destructive avalanche. Overall snowpack depths are variable across the region. It is generally shallower in the east.

Problems

Persistent Slabs

An icon showing Persistent Slabs
Forecasted warm air temperatures could increase the likelihood of triggering buried weak layers. The trees may not be the safe haven you expect: adopt a cautious attitude to all avalanche terrain.
Minimize overhead exposure during periods of warming and/or direct sun on starting zones.Back off if you encounter whumpfing, hollow sounds, or shooting cracks.Avoid open slopes and convex rolls where buried weak layers may be preserved.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs
Recent variable winds have redistributed loose snow into wind slabs on a range of aspects at higher elevations. A big enough wind slab release in the wrong location may have the force needed to trigger a deeper persistent weak layer.
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

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 16th, 2018 2:00PM