Avalanche Forecast

Issued: Feb 12th, 2020 4:00PM

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

Avalanche Canada mkoppang, Avalanche Canada

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Avalanche danger is forecast to be moderate on Thursday but if the winds increase overnight or earlier than forecast on thursday, we will begin to move into considerable. Pay attention to winds and influence of solar radiation on south facing slopes. 

Summary

Confidence

Moderate -

Weather Forecast

Warm temps (-6C for a daytime high) are forecast to continue into Thursday with clear skies in the morning. Later in the day, a low will begin to move into the region and light snowfall will start. Winds are forecast to increase with the arrival of the front into the strong range out of the SW around mid afternoon. Freezing levels in one forecast around said to be around 2000m while another says closer to valley bottom. Keep an eye on temps on Thursday. 

Avalanche Summary

A few loose dry avalanches from steeper terrain but no slab avalanche activity in the past 24hrs. 

Snowpack Summary

An additional 7-10cm of snow fell overnight. The slow trickle of snow is beginning to add up with around 20-25cm of recent snow over the past few days. Winds were forecast to be strong today but instead they were almost non existent. Having said this, there is some variable wind affect in alpine terrain along ridgecrests and in gullied features from earlier this week that skiers should be aware of. In addition to the windslab concern, the basal facets are still on our minds as we travel. Any snowpack test we do fails down at this interface down 1.5-2m. Think about the real possibility of an avalanche stepping down to this layer. If the sun comes out, also watch for cornices to begin to sag...

Terrain and Travel

  • Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Minimize overhead exposure; avalanches triggered by warming or cornice fall may be large and destructive.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong to extreme NW/W/SW winds have created a variety of wind slab conditions. In some areas these slabs will be sensitive to human triggering.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The weak basal layers are still a concern. An avalanche that occurred in the past 24 hours was a slide that stepped down to the basal layers and involved the entire snowpack. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3.5

Cornices

An icon showing Cornices

If the sun comes out with the forecasted warm temps, cornices may begin to sag and fail. 

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 3

Valid until: Feb 13th, 2020 4:00PM