Avalanche Forecast

Issued: Mar 31st, 2021 4:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

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Flurries and increasing winds should sustain wind slab problems at high elevations while light rain maintains some potential for wet loose activity lower down. Stay aware of cornices that formed fragile new growth during the storm. 

Summary

Confidence

Moderate -

Weather Forecast

Wednesday night: Brief clearing then cloudy. Strong southwest wind. Freezing level remaining near 1500 metres.

Thursday: Cloudy with flurries bringing around 5 cm of new snow, easing overnight. Strong southwest wind, easing over the day. Alpine high temperatures around -5 with freezing levels to 1500 metres.

Friday: Cloudy with continuing scattered flurries and up to 5 cm of new snow, continuing overnight. Light southwest wind. Alpine high temperatures around -5 with freezing levels to 1500 metres.

Saturday: Cloudy with continuing scattered flurries with less than 5 cm of new snow, continuing overnight. Light southwest winds. Alpine high temperatures around -4 with freezing levels to 1600 metres.

Avalanche Summary

We haven't received any reports of natural activity during the weekend's storm but a couple of involvements were reported on Monday. We really appreciate this MIN report of a size 1.5 skier triggered storm slab on a northeast aspect around treeline. Thankfully no one was injured. 

We regret to report a fatality on Eureka Peak, east of Williams Lake. A human-triggered cornice failure resulted in a size 2.5 slab avalanche. It is important to remember to stay well back from ridgetops that might be corniced and to avoid slopes with overhead cornice exposure especially under the current conditions where recent rapid growth has made them large and fragile.

Snowpack Summary

Thin new surface crusts have likely formed on some solar aspects and in a more widespread fashion below about 1900 metres. Forecast precipitation will likely keep surfaces wet at lower elevations while adding light amounts of dry snow to surfaces above 1500 metres. 

Our 20-50 cm of recent snow has otherwise seen some redistribution by southwest to northwest wind, and seems to be bonding well with underlying surfaces.

Recent warm weather patterns are expected to have helped old persistent weak layers heal including a few crusts buried over the last month, as well as a facet layer 150 cm deep from the mid-February cold snap, which has not produced avalanches since the first half of March.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Extra caution is needed around cornices under the current conditions.
  • The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
  • Be alert to conditions that change with elevation.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs are likely to be reactive in freshly wind loaded terrain features at upper elevations Thursday. Forecast strong winds and light new snow will add to this problem, forming new slabs and obscuring recent ones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

An icon showing Cornices

Cornices are fragile due to rapid growth from recent snow and wind. Cornice falls are dangerous in their own right and they can also trigger slabs on slopes below.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Loose Wet

An icon showing Loose Wet

A weak overnight refreeze coupled with light rain could maintain wet loose avalanche problems at lower elevations through Thursday. Back off from steep slopes where snow is wet and lacks cohesion.

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Apr 1st, 2021 4:00PM