Avalanche Forecast

Issued: Feb 7th, 2016 7:04AM

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

matt.mueller, Alberta Parks

Kananaskis.

We are now back into classic Considerable hazard for the time being. Wind slabs, persistent slabs and cornices will be lurking around in the terrain for the next little while. Pay attention to the spike in freezing levels on Tuesday in particular.

Summary

Confidence

Moderate - Freezing levels are uncertain on Tuesday

Weather Forecast

Mainly cloudy for Monday. No precipitation expected. Temperature in the alpine -3.0 and winds will be out of the west light to moderate (30km/h). Freezing level is expected to rise to 1900 meters.

Avalanche Summary

There was a natural cycle of avalanches of up to size 3.0 on Saturday due to the strong winds and warm temperatures. Avalanches up to size 2.5 were also accidentally and remotely triggered by skiers in treeline elevations on Saturday.

Snowpack Summary

In the upper snowpack (15-20 cm down) the storm interfaces are settling out quickly and bonding. However, there is great deal of variability in the distribution of the new snow due to the strong to extreme winds on Saturday. These winds have had a profound affect on the higher elevations at treeline and in the alpine where the winds were stronger. Wind slabs will exist that have denser properties and will be more prone to initiating fractures on the Jan 6th facet interface (40-70 cm down) and thus there is still big potential for these weaknesses to spread through the snowpack causing large and destructive avalanches. This January 6th facet layer will be a fixture in the snowpack for the next few weeks at the very least so don't let this weak layer fall off your radar any time soon.

Problems

Wind Slabs

Wind slabs will present in any open terrain, leeward terrain at treeline and above. The thickness of these slabs will be highly variable due to the very strong winds accompanied by the new snow.

Avoid freshly wind loaded features.>Avoid lee and cross-loaded terrain near ridge crests.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Persistent Slabs

Persistent slabs will be extensive except for places where the wind has cleaned the snow to rocks. The depth and density of the slab overlying the January 6th layer is highly variable depending on elevation and aspect resulting in a complex snowpack.

Extra caution needed around cornices with current conditions.>Avoid areas with overhead hazard.>Choose well supported terrain without convexities.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Storm Slabs

Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Feb 8th, 2016 2:00PM