Avalanche Forecast

Issued: Nov 29th, 2014 3:00PM

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

Alberta Parks mike.koppang, Alberta Parks

We are at the top end of Considerable right now and if winds increase and transport the new snow around, the danger will likely increase back to high.  Be very conservative at this time as the snowpack is very susceptible to human triggering.

Summary

Confidence

Fair

Weather Forecast

Cold temperatures are forecast to continue with light winds.  The most important this to pay attention to over the next few days will be the wind.  Currently the snowpack is touchy and with some increased winds, we can expect a natural avalanche cycle to again begin in most open wind affected areas.

Avalanche Summary

Evidence of a medium scale avalanche cycle with avalanches up to size 2 observed on all aspects.  We say a medium cycle because we were expecting to see more natural avalanches than we did.  A few loose dry avalanches were also observed out of steep rocky terrain. 

Snowpack Summary

50-60cm of snow has fallen over the past 72hrs with only areas of isolated wind affect.  The Nov24th facet layer is down 55cm and the Nov6th crust is down closer to 80cm.  Easy sheers persist within the storm snow and moderate sheers persist in a layer of facets overlying the Nov 6th crust.  The snowpack is very weak and unstable at this time.  Lots of cracking and whumpfing has been observed indicating that the current snowpack is unstable and susceptible to a human trigger.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slabs have the potential to step down to the Nov 6th crust and create a larger avalanche.  Lots of cracking and whumpfing indicating that the snowpack is unstable within the storm snow.
Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Avoid freshly wind loaded features.>Whumpfing is direct evidence of a buried instability.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 4

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
The current snowpack is very touchy.  Forecaster have low confidence in most open terrain that is steep enough to ski.
Avoid all avalanche terrain.>Use careful route-finding and stick to moderate slope angles with low consequences>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 4

Loose Dry

An icon showing Loose Dry
Watch for this problem around steep rocky terrain.
Be cautious of sluffing in steep terrain.>Avoid open slopes with any steepness over 40 degrees.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Valid until: Nov 30th, 2014 2:00PM