Avalanche Forecast

Issued: Mar 16th, 2022 4:00PM

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

Avalanche Canada rbuhler, Avalanche Canada

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New wind slab formation is expected on Thursday with new snowfall and strong southwest wind.

There is some uncertainty about the potential intensity of the storm. If you see more than 25 cm of new snow, expect a more widespread storm slab problem and higher local danger rating.

Summary

Confidence

Moderate - Uncertainty is due to the timing, track, & intensity of the incoming weather system.

Weather Forecast

A relatively weak storm system is expected to impact the region Wednesday night and Thursday morning. A break is then expected before the next system arrives Friday afternoon. 

Wednesday night: Snowfall 5-10 cm, strong SW wind, freezing level around 1000 m. 

Thursday: Snowfall 5-10 cm, strong SW wind, freezing level reaching around 1200 m. 

Friday and Friday night: Snowfall beginning in the afternoon 15-30 cm, moderate to strong SW wind, freezing level reaching around 1200 m. 

Saturday: A mix of sun and cloud, light to moderate variable wind, freezing level reaching around 1000 m. 

Avalanche Summary

No new avalanche observations have been reported since explosive control work on Sunday produced wind slab avalanches up to size 1.5. 

On Tuesday, the Avalanche Canada field team MIN report included evidence of wind distribution and potential wind slab formation in the alpine. Wind slabs are expected to continue to be a concern on Thursday at higher elevations with the forecast calling for new snow and strong wind. 

Snowpack Summary

Prior to Thursday's storm, 15-20 cm of recent snowfall had been redistributed by wind at upper elevations forming reactive wind slabs. The recent snow appears to be bonding well to a widespread melt-freeze crust found across the region. This underlying crust is thickest at low elevations and on sun-exposed slopes, and may not exist on high elevation north aspects. The snowpack is considered strong and well-bonded below this crust. 

Below treeline, snowpack depths are below threshold for avalanches in many areas.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid freshly wind loaded terrain features.
  • Wind slabs are most reactive during their formation.

Problems

Wind Slabs

An icon showing Wind Slabs

New wind slab formation is expected on Thursday with new snowfall and strong southwest wind. Older wind slabs which formed on the weekend may still be reactive in isolated areas. 

If you are seeing more than around 25 cm new snow accumulation along the immediate coastal areas, a more widespread storm slab problem may develop and the local avalanche danger may be higher than stated.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 17th, 2022 4:00PM