Avalanche Forecast

Issued: Dec 27th, 2023 4:00PM

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

Avalanche Canada isnowsell, Avalanche Canada

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A complex snowpack exists, with multiple layers of concern that may vary across different locations.

Summary

Confidence

Moderate

Avalanche Summary

On Monday, a size 1, skier-triggered persistent slab avalanche was reported in the Crawford area. It occurred on a northwest aspect at treeline.

There have been numerous natural and skier-triggered very large (up to size 3) persistent slab avalanches reported on all aspects at treeline and above in the Esplanade range over the past week. They've occurred on a layer of surface hoar down 50-70 cm.

Snowpack Summary

The upper snowpack continues to settle with mild temperatures and minimal wind.

A layer of buried surface hoar is down roughly 50 to 70 cm and remains concerning in much of the region. It is less of a concern in areas where a strong, supportive crust exists above the surface hoar layer.

As you move south in the region, weak facets near the ground are a concern. Especially in shallow, rocky areas in alpine terrain.

Average snowpack depths at treeline are 70-120 cm which tapers rapidly below treeline.

Weather Summary

Wednesday Night

Cloud building overnight with no precipitation, south alpine winds 0 to 20 km/h, treeline temperature -8 °C.

Thursday

Mostly cloudy with no precipitation, southwest alpine winds 0 to 20 km/h, treeline temperature -6 °C.

Friday

Mix of sun and cloud with no precipitation, southeast alpine winds 0 to 20 km/h, treeline temperature -6 °C.

Saturday

Mix of sun and cloud with no precipitation, southeast alpine winds 0 to 20 km/h, treeline temperature -4 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • In times of uncertainty conservative terrain choices are our best defense.
  • Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.

Problems

Persistent Slabs

An icon showing Persistent Slabs

The primary layer of concern in much of the region is a layer of surface hoar down 50-70 cm. If triggered, avalanches on this layer could step down to deeper weak layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A layer of weak facets near the ground may be reactive to human triggering. Especially in shallow, rocky areas in alpine terrain where the layer is not being capped by a crust.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Dec 28th, 2023 4:00PM