Avalanche forecast

Glacier

Jan 11 – 12, 2023Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low

Highlights

Persistent weak layers may be triggered from shallow, rocky areas. The resulting avalanche may start well away from where you are currently standing.

With this is mind, be mindful of other groups above and below. Remotely triggered avalanches ruin everyone's day!

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    10cm of snow and moderate Southerly winds Sunday night into Monday formed fresh wind slab in the alpine and into the tree line. If triggered these wind slabs could step down to deeper instabilities.

  • Persistent Slabs

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

    30-60cm of settled snow buries the Dec 23 facet interface. This layer will be a concern in thin rocky areas, on convex rolls, or in areas where the snowpack is unsupported.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    2–3.5

    The Nov 17 layer, down 60-120cm, consists of facets, a rotting crust in some locations, and decomposing surface hoar. Though becoming less likely to trigger, the resulting avalanche would be quite destructive.

Confidence

Moderate

Avalanche Summary

One sz 2 loose, solar-triggered avalanche was observed Monday in the Mannix path, stopping mid-path.

Several small loose sluffs (size 1 or less) from steep solar aspects were also observed during brief sunny periods on Monday.

Snowpack Summary

5-10cm of new snow has freshened up the surface. Small lenses of wind slab are found immediately on ridgetops and in their lee. This sits on a settled upper snowpack. There may be a thin sun crust on steep S-SW aspects from Monday's sunshine.

The December 23rd facet interface is down ~60cm and appears to be gaining strength, but remains a concern in shallow snowpack areas.

The November 17th facet/crust/surface hoar layer is down ~100cm and has become less reactive in snowpack tests. When it does fail, there is a dramatic 'drop' of the entire snow column. Spooky!

Weather Summary

There's a storm on the horizon, but things always look bigger from a distance! One more day of calm, then a warm, wet storm on Thurs/Fri.

Wed: mix of sun/cloud, Alp high -4*C, 1200m FZL, light SW ridge winds

Thurs: snow and rising temps later in the afternoon, 10-15cm, Alp high -1*C, 1600m FZL, mod/strong SW ridge winds

Fri: flurries, 10cm, Alp high -1*C, 1800-2000m FZL, light to gusty moderate SW ridge winds

Terrain and Travel Advice

  • Be carefull around freshly wind loaded features.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regions covered