Avalanche Forecast

Issued: Jan 9th, 2022 4:00PM

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

Avalanche Canada dboucher, Avalanche Canada

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Warm temperature, new precipitation and high wind will continue to develop wind slabs that may remain possible for humans to trigger.

Summary

Confidence

Moderate -

Weather Forecast

An unstable onshore flow will give flurries to the BC coast with showers below 1000 metres. 

SUNDAY NIGHT: A few clouds, no precipitation, 20-40 km/h south wind, alpine temperature -2 C with freezing level at 1500 m in the north and 2500 m in the south.

MONDAY: Periods of snow beginning in the morning, accumulation 5 to 10 cm above 1000 m and rain below, 40-60 km/h south wind, alpine temperature -3 C.

TUESDAY: Snow and rain mixed, accumulation 5 to 10 cm, 40-60 km/h southwest wind, alpine temperature 0 C with freezing level at 1800 m.

WEDNESDAY: Snow and rain mixed, accumulation 5 to 10 cm, 50-60 km/h southwest wind, alpine temperature +1 C with freezing level at 1900 m.

Avalanche Summary

A few natural avalanches were observed over the last few days, including wind slab avalanches at higher elevation and loose avalanches at lower elevations. With warm temperature, new precipitation and high wind, it may remain possible for humans to trigger slabs in lee terrain features in alpine and treeline.

Snowpack Summary

The last few days snowfall (20-40 cm) were associated with strong southwest wind, which formed widespread new wind slabs in lee terrain features in alpine and treeline. This recent precipitation adds to the 50+ cm of snow that has fallen since January 1, which may overly sugary faceted grains that formed during the cold spell in late December.

Around 80 to 200 cm deep, a weak layer of faceted grains may be found above a melt-freeze crust that formed in early December. The layer is most prominent between 1700 and 2100 m. Observed avalanches on this layer are sporadic and isolated, suggesting that this layer has become dormant. The most likely place to trigger it would be in thin, rocky snowpack areas.

The lower snowpack is well-settled and strong.

Terrain and Travel

  • Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
  • Wind slabs are most reactive during their formation.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs will continue to develop with new snow and strong southerly wind and may remain reactive to human traffic. Expect to find them in steep, lee terrain features near ridges.  

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Jan 10th, 2022 4:00PM