Archived

Avalanche Forecast

Nov 29th, 2011–Dec 2nd, 2011

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Waterton Lakes.

Although avalanche danger has fallen from last week, deep instabilities are still present. Travel conditions are challenging. Below 1900m all aspects are covered in crust. Wind slabs are on all lees slopes and any SW aspect has been stripped bare.

Avalanche Problems

Wind Slabs

Extreme SW wind over the weekend have created the potential for surface slabs over this heavier midpack. 10cm is forecast for the next 24 hrs with NE winds. Avalanche danger should not increase significantly unless we get more than forecast.

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

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 2

Deep Persistent Slabs

Numerous slab avalanches occurred during the storm last week, failing on basal crusts and weak layers near the ground. This problem still persists but triggering it seems difficult. However, any avalanche activity on this layer will be destructive.

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4