Avalanche Forecast

Issued: Mar 13th, 2019 8:00AM

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

Parks Canada chris gooliaff, Parks Canada

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The strong March sun, beating down on steep solar aspects, may be the natural trigger to start an avalanche above you. With freezing levels beginning to rise, now is the time to start and finish your day early.

Summary

Weather Forecast

It is mid-March and the sun is packing a strong punch. Today, the forecast is sunny with cloudy periods, alpine high of -9*C, and light westerly ridge-top winds. Expect more clouds Thursday, along with moderate SW winds. Today and tomorrow, freezing levels should rise in the afternoon to 1200m.

Snowpack Summary

Roughly 50cm of snow has fallen at tree-line over the last week. Moderate winds and mild temp's have created a cohesive soft slab which sits on a plethora of old surfaces including; sun crusts on solar aspects; hard wind slab in exposed areas; and surface facets in sheltered locations.

Avalanche Summary

A natural avalanche in the highway corridor yesterday. Numerous natural avalanches from sz 1.5 to 3 were observed from Macdonald and Tupper in most of their paths. All 13 explosive charges produced sz 2-2.5 avalanches on Fidelity, Fortitude, and Cutbank. Field teams were able to ski control sz 1 soft slabs on convexities at tree-line.

Confidence

Due to the number of field observations

Problems

Storm Slabs

An icon showing Storm Slabs
45-50cm of new snow over the last week has become a cohesive soft slab in the Alpine and exposed areas of Tree Line. Storm slabs may be overlying weak faceted snow, old wind slabs, or a sun crust. The bond to these old surfaces is variable.
Use caution in alpine and open treeline lees. Recent snowfall has created storm slabs.Convex features and steep unsupported slopes will be most prone to triggering.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Loose Dry

An icon showing Loose Dry
When the sun makes an appearance today, steep solar aspects will shed the new snow. Skiers will likely be able to trigger loose dry slides on steep unsupported terrain features from all aspects.
Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 14th, 2019 8:00AM