Avalanche Forecast

Issued: Mar 4th, 2020 4:00PM

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

Avalanche Canada JMackenzie, Avalanche Canada

New snow and persistent strong winds have raised the avalanche danger. Stick to conservative terrain and avoid overhead hazard.

Summary

Confidence

Moderate -

Weather Forecast

Thursday should bring a mix of sun and cloud with winds out of the SW at 80km/h. Temperatures are expected to reach -4 in the Alpine. Friday and Saturday look snowy with as much as 25cm falling over the course of those two days.

Avalanche Summary

Given the recent intense wind loading, there has been a surprising lack of natural avalanche activity. The snowpack is nearing a tipping point, and a natural avalanche cycle is expected to begin in the near future.

Snowpack Summary

Another 15cm of new snow in past 24 hours brings recent storm snow totals to near 45cm. Extreme westerly winds have stripped west aspects down to bare rock and redistributed significant amounts of snow on N, NE and E aspects. Expect extensive wind slab development on lee and cross-loaded features. These slabs could easily be 100cm deep in places. Human triggering is very likely and a natural avalanche cycle is a real possibility in the next couple of days.

Terrain and Travel

  • Avoid all avalanche terrain during periods of strong wind.
  • Be aware of the potential for large avalanches due to the presence of a deep persistent slab.
  • Minimize exposure during periods of heavy loading from new snow and wind.
  • Avoid lee and cross-loaded slopes at and above treeline.
  • Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.

Problems

Wind Slabs

An icon showing Wind Slabs

Extensive wind slab development continues. Human triggering is very likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices

Cornices are large in many areas, and if triggered may release and wind slab or a deep persistent slab on the slopes below.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1.5 - 3

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Deep persistent slabs may be triggered by a large trigger such as a cornice fall. Be especially cautious in shallow snowpack areas where triggering is easier.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Mar 5th, 2020 4:00PM