Avalanche Forecast

Issued: Dec 26th, 2014 4:00PM

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

a.l. horton, Parks Canada

Jasper.

Loose snow sluffing out of steep rocky alpine terrain will be a concern for ice climbers.

Summary

Weather Forecast

Increasing NW winds overnight with 3-6 cm of snow. Cool temperatures. Skies clear on Sunday with light NW winds dropping temperatures in to low -20's.

Snowpack Summary

New wind slab forming from reverse loading Northerly winds along cross-loaded gulley features. The interface between the strong mid-pack and weaker basal facets is most susceptible to human triggering from shallow rocky areas.

Avalanche Summary

Very thin loose snow avalanches observed on East and West alpine aspects from steep rocky terrain. Some very thin slab avalanches (Size 0.5) on reversed cross-loaded gulley features.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Sunday

Problems

Wind Slabs

Northerly winds reverse loading cross-loaded gulley features. Previous wind slab from SW winds appear to be well bonded to snow below.

Be cautious as you transition into wind affected terrain.Avoid travelling in areas that have been reverse loaded by winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

This weak layer exists below a strong mid-pack at treeline and sub-alpine elevations. Large loads such as surface slides or cornice collapse could trigger this deep persistent weakness.

Carefully evaluate and use caution around thin snowpack areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 27th, 2014 4:00PM