Avalanche Forecast

Issued: Jan 10th, 2014 7:19AM

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

Alberta Parks matt.mueller, Alberta Parks

Things will change very quickly with the wind and new snow. Keep a constant eye out for changing conditions, especially in the alpine. Cornices, spindrift and sluffing will all become a concern. Low elevation rain may pose a threat as well.

Summary

Confidence

Good

Weather Forecast

The snow is coming! Forecasts now agree that a strong low pressure over BC will move far enough east to give the Spray Valley as much as 58 cm of snow by Monday afternoon. Lets hope... Of course the winds will arrive with this storm. The alpine winds will be sustained at 80-110 km/hr for Saturday. Valley bottom winds will be 25-35km/hr. Saturday's high is slightly above zero at 1500m.

Avalanche Summary

No new avalanches noted today. However the visibility was poor. Spindrift was noted near alpine ridgelines.

Snowpack Summary

Trace amounts of new snow overnight have already combined with the winds to start forming storm slabsĀ  at the alpine and upper treeline areas. Cornices are appearing here as well. Near treeline ridges the winds have created a series of thin windslabs that are lamintaed together. Over all this layer 60cm thick. Below this hodge podge of windslabs are the facets from the cold snap awhile back. This interface is obvious and reacted to stability tests. The facet layer goes to ground. The october crust has rotted out and made depth hoar and facets now. It was on the ground and had no structure to it.

Problems

Loose Dry

An icon showing Loose Dry
This intense storm will quickly drop 25cm's of new snow by noon tomorrow. Any sluffing will entrain existing snow, making for significant sized avalanches. Avoid terrain traps and give overhead cliffs a wide berth.
Avoid travelling under cliffs that are exposed to sluffing from above.>Be cautious of sluffing in steep terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Storm Slabs

An icon showing Storm Slabs
These new slabs have already begun forming with today's new snow. Immediate lees are increasingly suspect as the new snow comes in. These will build quickly with the relatively warm temps and high winds.
Avoid freshly wind loaded features.>Choose well supported terrain without convexities.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
The new load will stress this layer. There is a good chance it will not be able to support the load. Given how stiff the upper layers are wide propagations are likely. Especially in areas that have not already avalanched. Avoid large features.
Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 6

Valid until: Jan 11th, 2014 2:00PM