Avalanche Forecast

Issued: Mar 19th, 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, Loose Wet and Deep Persistent Slabs.

Avalanche Canada mkoppang, Avalanche Canada

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Please make conservative choices. Now is not the time for an accident. The current pandemic is overloading the medical system and could affect backcountry rescue response. Intense solar radiation will decrease stability later in the day especially on solar aspects.

Summary

Confidence

Moderate -

Weather Forecast

Cloudy conditions overnight will help keep temps warmer before clear skies prevail tomorrow around mid day. No new snow is forecast and freezing levels are expected to be around 2200m. Watch for solar radiation to decrease stability especially on solar aspects. 

Avalanche Summary

No new avalanche observations on Thursday but observations were also limited. 

Snowpack Summary

A dusting of recent snow overlies a sun crust on solar aspects and previously formed wind slabs everywhere else. These buried wind slabs are found at all elevations and extend into open areas all the way to valley floor. The slabs are failing at a depth of about 20cm, which is making for generally poor quality skiing. Cornices are larger than normal. Although they haven't been active recently, any corniced area or slopes below should be avoided. Stability changes during the day based on incoming solar radiation. As the snowpack warms up, it becomes less stable. These decreases in stability on most noteable on steep solar aspects so plan you trip to avoid these areas later in the day.

Terrain and Travel

  • Avoid convexities, steep unsupported terrain and rocky outcroppings.
  • Cornices become weak with daytime heating, travel early on exposed slopes.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Avoid exposure to slopes that have cornices overhead.
  • Be aware of the potential for large avalanches due to the presence of a deep persistent slab.
  • Avoid steep slopes when air temperatures are warm, or solar radiation is strong.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs seem to be everywhere. They are most concerning for human triggering in steep, convex and unsupported terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 2.5

Loose Wet

An icon showing Loose Wet

Loose wet slides will start in the PM with daytime warming. Steep solar slopes especially in thinner areas will be places to avoid. Any small slide may step down to the deeper basal layers. 

Aspects: South, South West, West.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The deep persistent layer is still a concern, especially in shallow snowpack areas. A large cornice trigger could also be enough to weak up this layer.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1.5 - 3.5

Valid until: Mar 20th, 2020 4:00PM