Avalanche Forecast

Issued: Mar 9th, 2024 4:00PM

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

Avalanche Canada JH, Avalanche Canada

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We haven't had significant snowfall in a while, but it is not time to start stepping out yet.

Skiers/riders could still trigger large avalanches on the persistent weak layer.

Make plans to ski conservative slopes with limited overhead exposure, and stick to them.

Summary

Confidence

Moderate

Avalanche Summary

Saturday, there were a few size 1.5-2.5 natural avalanches triggered by the wind in the steep terrain above the highway corridor East of the pass.

Thursday, we observed fresh naturally triggered size 3 slab avalanches from Catamount Mtn SE face and Mt. Leda NE face. These were both deep, likley failing on the Feb 3rd crust.

We continue to see daily reports in the region of human triggered avalanches on the Feb 3rd layer.

Snowpack Summary

Incoming new snow covers a thin suncrust on South & West aspects, previous wind effect from variable winds in open terrain, and settled powder in sheltered areas.

80-140cm of settled snow sits atop a sugary facet layer. These facets are not bonding well to the widespread, very firm crust from Feb 3rd. This crust is a significant persistent weak layer and will be the main layer of concern for the foreseeable future.

Weather Summary

A couple of weak cold fronts moving inland give snow flurries and gusty winds tonight and again Sunday evening.

Tonight: Flurries (5cm). Alpine low -8°C. Strong gusty SW ridgetop winds.

Sun: Flurries (~5cm). High -5°C. Freezing level (FZL) 1500m. Gusty mod SW winds.

Mon: Flurries (5-10cm). Low -8°C, High -6°C. FZL 1300m. Gusty moderate S winds.

Tues: Flurries (~5cm). Low -9°C, High -5°C. FZL 1500m. Light winds.

Terrain and Travel Advice

  • Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
  • Remote triggering is a concern, avoid terrain where triggering slopes from below is possible
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Persistent Slabs

An icon showing Persistent Slabs

This crust-facet combo (Feb 3rd) was created by a rain event followed by an extended cold, clear period without snow earlier this month. 80-140cm now sits on the persistent weak layer. Human triggered avalanches on this layer remain possible, and resulting avalanches could be very large in size.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Wind Slabs

An icon showing Wind Slabs

Just as old windslabs are becoming less reactive, increasing winds Saturday into Sunday will refresh this problem. Expect increasing reactivity in the immediate lees of alpine ridges or cross loaded areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 10th, 2024 5:00PM

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