Avalanche forecast

Glacier

Jan 26 – 27, 2023Avalanche Canada
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Avalanche danger

Sat
Sun
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate

Highlights

Watch for fresh wind slabs forming Thursday with new snow and winds forecast. These could be touchy to rider triggering.

Use caution in shallow, rocky areas for triggering a weak layer at the base of the snowpack.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2.5

    Moderate westerly winds forecast on Thursday will build upon wind slabs formed earlier in the week.

    These slabs are particularly reactive on convex rolls at ridge-line, lee areas, and cross loaded features.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2.5

    This layer is buried ~40cm and will be most reactive at ridgeline or in open lee features where new wind slab has formed on top of it. If triggered, this slab has the potential to step down to the deep persistent layer.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    2–4

    The Nov 17 layer, which consists of a faceted crust and decomposing surface hoar, highlights a weak basal snowpack. Be cautious in steep, rocky areas with thin snow coverage, where the majority of the snowpack is weak and faceted.

Confidence

Moderate

Avalanche Summary

On Wednesday we observed several natural avalanches, size 2-2.5 along the highway corridor in south facing terrain. Likely triggered by wind loading and sun effect midday.

Backcountry reports, also on Wednesday, of rider triggering soft slabs, up to size 1, down 30-40cm on a sun crust. And sluffing in steep terrain.

A field team on Connaught/Lookout triggered a sz 1 wind slab on Monday, which stepped down to the Jan 3 surface hoar. They also observed several sz 1 loose/dry avalanches on the N Face of MacDonald, running in extreme terrain.

Cheops North 4 ran sz 2 Monday morning, while Frequent Flyer ran sz 2 on Sat into the creek.

Near neighbours have reported large natural and rider triggered avalanches up to sz 3, both wind slabs and deep persistent slabs. See MIN's for details.

Snowpack Summary

Reactive wind slabs are popping out at Treeline and Alpine elevations, stepping down into the Jan 3 persistent weak layer. Thin sun crust down 30-40cm. Good skiing below treeline with small amounts of unconsolidated storm snow keeping the surface soft.

The mid-pack facets are slowly rounding and gaining strength, while the basal facets and Nov 17 facet/SH/crust weakness are still reactive when isolated in snowpack tests.

Weather Summary

Unsettled weather Thurs/Fri with flurries bringing light/moderate snowfall and light/mod W/NW winds.

Tonight: Cloudy w/flurries, 2 cm, Snow level 800m lowering to valley bottom this evening, Moderate W winds.

Thurs: Cloudy w/flurries, Alp high -4*C, 1500m FZL, moderate gusty W winds

Fri: flurries, 5-10cm snow, Alp high -6*C, 1200m FZL, moderate gusty N winds

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regions covered