Archived

Avalanche Forecast

Mar 11th, 2021–Mar 14th, 2021

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

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

4: High

The avalanche danger rating at treeline will be high

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Waterton Lakes.

Another spike in temperatures will destabilize the snowpack this weekend. Start your day early, minimize overhead hazard, and end before the surface crust breaks down.

The next bulletin will be issued Thursday, March 18.

Weather Forecast

We will experience rapid warming this weekend, with freezing levels rising to 2600m on Saturday, and 3000m on Sunday. Paired with sunny skies this will rapidly destabilize the snowpack, but temperatures should dip to near valley bottom overnight offering limited recovery. Winds will generally be light from the southwest.

Snowpack Summary

A crust exists on the surface to ridgetop on solar aspects and at low elevations breaking down during the day. This tops 30-50cm dense snow above of the Feb 14 facet layer which is above hard surfaces in most places. The remainder of the midpack is made up of dense facets and decomposing crusts, with early season ice crusts forming the base.

Avalanche Summary

No new avalanches observed this week, but we expect that to change as freezing levels rise again through the weekend.

Confidence

The weather pattern is stable

Avalanche Problems

Persistent Slabs

This problem is most prevalent at and below treeline where it exists as a prominent facet layer down 30-70. Rapidly rising temperatures will likely trigger natural avalanches on this layer with potential for wide propagation.

Be aware of the potential for wide propagations which could result in large avalanches.
Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 2 - 3

Loose Wet

The sun is packing a punch these days, and surface snow will quickly destabilize on steep solar aspects when it comes out.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: South East, South, South West.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2

Cornices

Cornices have grown quite large. It's hard to predict when one might fall, but rising temperatures and strong sunshine will make it much more likely.

Avoid travel on slopes that are exposed to cornices overhead.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2.5