Avalanche Forecast

Issued: Feb 2nd, 2023 4:00PM

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

Avalanche Canada dnylen, Avalanche Canada

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Sheltered terrain in the alpine has a persistent weak layer that will be a concern for awhile still. It has shown the ability to remote trigger from quite far away.

Usual signs of instability may not be present in areas of concern. Be wary of large and continuous north facing slopes.

Summary

Confidence

Moderate

Avalanche Summary

A couple of large (size 2-3) persistent slab, human-triggered and natural avalanches have been reported within the last 7 days. Avalanches have occurred near ridgetops in north-to-northeast alpine terrain. These avalanches have shown an impressive capability of propagating large distances. Here is a link to the most recent human-triggered size 3 avalanche.

If you are out in the backcountry please consider filling out a Mountain Information Network report.

Snowpack Summary

5 cm of new light snow is resting on a variety of wind-affected surfaces and crusts with small surface hoar in places in the alpine. This new layer should be monitored closely moving forward as new snow arrives early next week.

A persistent weak layer of surface hoar and/or facets is 50-80 cm deep and exists in north facing alpine features, creating a number of recent, scary human-triggered avalanches.

Below roughly 1700 m a widespread 5-20 cm, supportive, melt-freeze crust is present,

Weather Summary

Thursday night

Cloudy. 3 cm of new snow. Temperature -9 C overnight. Variable and light winds.

Friday

Mostly cloudy. 1 cm new snow. Temperature rising to -6 C in the afternoon. Wind 20 km/h from the southwest.

Saturday

Mostly cloudy. No new snow. Temperature -6C. Wind 30 km/h from the southwest.

Sunday

Mostly cloudy. Flurries possible. Temperature -4 Wind 50 km/h from the southwest.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • In times of uncertainty conservative terrain choices are our best defense.
  • Use caution on large alpine slopes, especially around thin areas that may propagate to deeper instabilities.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Persistent slabs have potential to pull back to lower angle terrain.

Problems

Persistent Slabs

An icon showing Persistent Slabs

Buried weak layers have recently produced large, surprising avalanches. The most recent avalanche activity has been observed on north to northeast alpine terrain on preserved surface hoar buried 50-80cm. Keep in mind the potential for remotely triggered avalanches and how far these large avalanches can run into flatter terrain. Also keep in mind that stiff slabs can pull back into flatter terrain above them. These layers will be easier to trigger where the snowpack is thin.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 3

Valid until: Feb 3rd, 2023 4:00PM