Avalanche Forecast

Issued: Nov 27th, 2021 4:00PM

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

Avalanche Canada bchristie, Avalanche Canada

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Continuing storms will keep avalanche hazard elevated. Carefully consider terrain above you. Natural avalanches are becoming more likely.

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Stormy weather through the next few days, with the most severe weather forecast to hit on Tuesday.

SATURDAY NIGHT: Overcast. Freezing level rises to 1400 m. Moderate wind from the southwest, trending to strong or extreme as you move further north in the region. 5-20 cm snow expected, with the higher amounts falling at higher elevations.

SUNDAY: Overcast. Freezing level 1400 m. Moderate wind from the southwest, trending to strong or extreme as you move further north in the region. Steady snowfall, 10-15 cm.

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MONDAY: Possible breaks in the cloud cover. Freezing level at 1400 m, with the possibility of dropping to valley bottom in the north end of the region. Moderate to strong southwest wind through the day, trending towards extreme in the afternoon. 0-5 cm snow during the day, with heavier snowfall starting in the evening. 

TUESDAY: Overcast. Freezing level rising through the day to 1700 m. Extreme southwest wind. 17-35 cm of snow expected.  

Avalanche Summary

Saturday, a rider was caught in an avalanche in the Pine Pass area. Search and rescue response is ongoing, but no other details were available at the time of publishing. 

There is evidence that an avalanche cycle occurred in the north of the region on Thursday. Avalanches ranged from size 1 to size 2.5, with the majority starting around treeline.

If you are getting out in the mountains, we strongly encourage people to share observations on the Mountain Information Network.

Snowpack Summary

Recent winds have scoured exposed ridges, and loaded lee slopes. You may see this trend continue with today's snow and wind.

In areas sheltered from the wind, new storm slabs will likely be forming on all aspects.

At elevations below treeline that saw rain earlier in the week, the new storm snow will be covering a crust that formed overnight on Friday. 

Recent observations suggest snow depths below treeline are around 75-100 cm with very little snow below 1400 m. Expect the alpine snowpack to be 150 cm or more.

 

In the Pine Pass area, expect to find a deeper snowpack than the rest of the region. The last storm dropped up to 80 cm of snow there over 2 days. 

The lower snowpack mostly consists of a series of early season crusts. These appear to be strong, but shallow alpine slopes along the eastern side of the Rockies towards Jasper may have weaker, faceted snow near the ground.

Terrain and Travel

  • Avoid freshly wind loaded terrain features.
  • Remember that the snowpack will be significantly different at higher elevations than lower down.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

Problems

Storm Slabs

An icon showing Storm Slabs

Areas like Pine Pass that got more snow in the last week have the potential to produce bigger avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Valid until: Nov 28th, 2021 4:00PM