Avalanche Forecast

Issued: Jan 12th, 2024 4:00PM

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

Avalanche Canada dnylen, Avalanche Canada

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It's cold... If you do decide to head out, stick to easier and shorter objectives.

Carefully consider the terrain you are travelling in as there are avalanche problems at all elevations.

Summary

Confidence

Moderate

Avalanche Summary

On Thursday, multiple large explosive controlled avalanches to size 3 were reported in the region that had impressive propagation. Wednesday avalanche reports documented a natural storm slab cycle averaging size 1-2, with a few size 2.5 avalanches.

Snowpack Summary

Roughly 30-40 cm of new snow fell in the region Monday night through Tuesday. It buried moderately wind-affected snow in exposed areas at higher elevations and otherwise added to about 50 cm of recent storm snow. All this snow overlies a variety of old surfaces, but sheltered terrain where it may overlie preserved surface hoar, is the most concerning. Below 1600m a crust is present beneath the storm snow.

Two additional surface hoar layers in the top 2 m of the snowpack are diminishing in importance. The deeper of the two likely has a robust crust above it, below treeline. The depth of the snowpack varies greatly throughout the region and weak basal facets are present at the base of the snowpack.

Weather Summary

Friday Night

Clear. Northwest alpine wind 10-30 km/h. Treeline temperature -33°C.

Saturday

Sunny. Variable alpine wind 10 -30 km/h. Treeline temperature -25°C.

Sunday

Partially cloudy. Northwest alpine wind 20-40 km/h. Treeline temperature -23°C.

Monday

Sunny. Northwest alpine wind 30-60 km/h. Treeline temperature -25°C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.

Problems

Wind Slabs

An icon showing Wind Slabs

Watch for signs of slab formation in the new snow, particularly in wind-affected areas and where buried surface hoar could be preserved (think sheltered openings at mid elevations).

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Storm Slabs

An icon showing Storm Slabs

Recent storm snow covers a crust and isolated surface hoar. Investigate this interface. As the fresh snow settles and gains cohesion, a reactive upper snowpack may develop.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Basal facets remain a real concern in steep, rocky terrain and other alpine features with thin-to-thick snowpack transitions. Recent avalanche activity tells us this problem is still lurking out there.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Jan 13th, 2024 4:00PM