Avalanche Forecast

Issued: Feb 16th, 2015 8:09AM

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

matt.mueller, Alberta Parks

Kananaskis.

The stabilization process is taking its time with the last storm interface. Avoiding avalanche terrain makes sense right now. The SPAW is still in effect for Tues. Click the link for details or the facebook page.

Summary

Confidence

Good

Weather Forecast

Mixed skies are on for tomorrow. The sun has started to pack a punch lately, so expect a fair amount of solar heating. The ambient high at 2500m will be around -5. Ridge winds will range from 10-30 km/hr from the west. The general pattern continues to be from the north west with a slight northerly shift on Wed.

Avalanche Summary

There are many avalanches out there at the moment. A very large natural avalanche was noted today on Mt. Worthington. Sz3.5, 2700m, SE aspect, 50 degree slope, 1.5m deep by 500m wide. Unknown trigger.

Snowpack Summary

Valley bottom saw a dusting overnight, nothing significant enough to change the conditions. There is a 2cm thick breakable, temperature crust that extends up to the 2100m mark. This is likely higher on south & south-west aspects. The snowpack doesn't gain any significant structure until 2000-2100 meter mark. At that point the midpack gains strength, but the weak bottom layers are present. Treeline has a variety of buried windslabs that are sitting on the Jan 31st layer. The depth of this layer varies greatly. In windloaded terrain it is down as much as 120cm's, and in more windward areas it is down 40-60cm's. Any recent activity has initiated on this layer and quickly stepped to the deeper, basal layers. The alpine has more widespread windloading with the typical crossloading pattern.

Problems

Wind Slabs

This layer continues to produce unexpectedly large avalanches. The reactivity of this layer is very difficult to predict. The best option right now is to avoid any situation where you have to trust this layer. Choose small, supported terrain.

Avoid exposure to solar aspects overhead, large avalanches may reach the end of run out zones.>Minimize overhead exposure; avalanches triggered by windloading may reach run out zones.>Avoid cross loaded slopes at or above treeline.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 5

Deep Persistent Slabs

This problem commands a lot of respect. Avalanches stepping down can entrain large amounts of snow right now making for large destructive avalanches. Large triggers should be a concern right now.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Avoid lingering in runout zones.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

3 - 6

Valid until: Feb 17th, 2015 2:00PM