Avalanche Forecast

Issued: Dec 14th, 2021 1:00PM

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

VIAC JSmith, VIAC

Forecast snow and wind are expected to form fresh storm slabs reactive to human triggers on Wednesday.

 Use small low consequence slopes to test the bond of the new snow. 

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain.

Weather Forecast

TUESDAY NIGHT: Snow; 5-15 cm / Strong, southerly winds / Low of -4 C / Freezing level 500 m.

WEDNESDAY: Snow; 15-25 cm / Strong, southerly winds / High of 0 C / Freezing level 700 m.

THURSDAY: Mix of sun and cloud / Moderate, northwesterly winds / High of 0 C / Freezing level 700 m.

FRIDAY: Increasing cloudiness with flurries; 3-5 cm / Light, westerly winds / High of -2 C / Freezing level 500 m.

Avalanche Summary

Forecast snow and wind are expected to form fresh storm slabs reactive to human triggers on Wednesday.

Snowpack Summary

An impressive storm over the weekend brought 50-90 cm of snow to the mountains. A gradual rise in temperature during the storm formed a crust layer that can be found in areas up to 1400 m. An additional 20-50 cm of snow has accumulated since temperatures cooled. 

Strong southerly winds have had an ample supply of snow to drift into wind slabs at upper elevations. It remains possible to trigger these wind slabs in lee terrain features, such as down-wind of ridges and roll-overs.

Monitor for changing conditions as you move into wind-exposed terrain and pay attention to cracking or hollow sounds.

Below the early December crust layers, the snowpack is generally well-settled. With this storm event, a greater number of areas below treeline are exceeding threshold snow depths for avalanches. 

Terrain and Travel

  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Use small low consequence slopes to test the bond of the new snow.
  • Be careful to keep storm day fever from luring you out into bigger terrain features.
  • Avoid terrain traps where the consequence of any avalanche could be serious.

Problems

Storm Slabs

An icon showing Storm Slabs

Forecast snow and wind are expected to form fresh storm slabs reactive to human triggers on Wednesday.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Dec 15th, 2021 1:00PM