Avalanche Forecast

Issued: Dec 2nd, 2018 3:52PM

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

Avalanche Canada cgarritty, Avalanche Canada

We're on a positive track with last week's avalanche problems mostly stabilized, but you can likely still find trouble spots of wind slab and cornice in the alpine.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Sunday night: Cloudy with clear periods. Light north winds.Monday: A mix of sun and cloud. Light northeast winds, increasing over the day. Alpine high temperatures around -10.Tuesday: Mainly sunny with some valley cloud. Light northwest winds. Alpine high temperatures rising to around -2 under a mild temperature inversion.Wednesday: Sunny. Light northeast winds. Alpine high temperatures to around -3 under a mild temperature inversion.

Avalanche Summary

Two recent very large (size 3) avalanches were observed in the Joffre Lakes area on Saturday. These released from the high alpine northeast and northwest faces of Mt. Joffre and Mt. Matier, respectively. The evidence of the Mt. Matier slide features several 'step downs' as the slide progressively triggered deeper layers of the snowpack, all the way down to previous summer snow cover. Both slides likely released during last week's storm.Please submit any observations you have to the Mountain Information Network here.

Snowpack Summary

The storm from early last week produced ample precipitation, however it mostly fell as rain. Extreme out of the south and southwest likely produced widespread cornices and wind slabs in lee terrain during the storm. These problems are expected to be on a positive track toward stabilizing.A MIN from Friday suggests that it's skiable from about 1600 metres on up. Between 1600 and 2000 m there is 5 to 10 cm of low density snow over a 5 cm breakable crust. Above 2000m is reportedly skiing well and alpine snowpack depths are approaching 175 cm. Near the ground there is a crust/facet interface. Although little is known about the reactivity of this layer, recent observations in the north of the region show that it was reactive during last week's storm. It is thought that there is insufficient snow for avalanches below 1500 m.

Problems

Wind Slabs

An icon showing Wind Slabs
If there's any good riding/travel to be had, it's going to be in the alpine. This is also where you're most likely to find pockets of wind slab that could remain sensitive to human triggering.
Be cautious around mid-slope terrain features like ridges and ribs where slabs may be deeper.The deepest slabs will be found immediately lee of ridge-crest.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Cornices

An icon showing Cornices
Cornices have likely formed along alpine ridgelines. Cornices are inherently weak and can fail under the weight of a person or group.
Be wary of traveling on slopes that are exposed to cornices overhead.Stay well back from cornices when traveling on ridgelines.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 3rd, 2018 2:00PM