Avalanche Forecast

Issued: Jan 30th, 2023 4:00PM

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

Avalanche Canada JA, Avalanche Canada

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The weak base of our snowpack will persist even when the signs indicate an improving trend. Maintain your discipline to not push into bigger terrain.

Summary

Confidence

Moderate

Avalanche Summary

Highway 93 patrol on Sunday noted isolated wind slab activity to size 1.5 and several deep persistent slab avalanches up to size 2.5 in the alpine on southerly aspects likely occurring Friday and Saturday.

Of note is how sensitive the deep persistent problem is to additional load i.e. 10mm of precipitation with wind was enough to initiate a significant cycle on this layer.

Don't forget to post avalanche observations to the MIN.

Snowpack Summary

10 to 20cm of soft settled new snow from Jan 27th overlies a weak melt-freeze crust up to 2000m. Wind slabs are present in the alpine and exposed tree line locations. Generally, the bottom of the snowpack is weak facets and depth hoar. The snowpack ranges from 50 to 120cm.

Weather Summary

Transitioning from cold Arctic air back to a westerly flow. Tuesday a series of weak low pressure systems and troughs will bring isolated to light precipitation through the remainder of the week. Up to 10mm is possible by Friday. Temperatures will be seasonal trending milder towards the weekend. Winds will be consistent light to moderate values from the west.

Detailed weather forecasts from Avalanche Canada: https://www.avalanche.ca/weather/forecast

Terrain and Travel Advice

  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The bottom of the snow pack is inherently weak with well developed Facets and Depth Hoar. Avalanches initiating in the upper snowpack are likely to step down to this layer and gain significant mass.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 3

Wind Slabs

An icon showing Wind Slabs

North winds at ridge top created wind slabs on Southerly slopes which don't typically see wind loading. The wind slabs from previous moderate to strong SW winds are also still present.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 31st, 2023 4:00PM