Avalanche Forecast

Issued: Feb 19th, 2022 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

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Keep terrain selection conservative as storm snow accumulates, expect the new snow to bond poorly to old snow surfaces.

Avoid avalanche terrain and exposure to overhead hazard during peak snowfall.

Summary

Confidence

Moderate - We are confident a natural avalanche cycle will begin shortly after the arrival of the incoming weather. Forecast snowfall amounts are uncertain.

Weather Forecast

SATURDAY NIGHT: 10-15 cm by morning. Freezing levels drop to valley bottom. Winds ease to moderate from the east.

SUNDAY: Snowfall continues with another 10-20 cm of snow possible over the day, light northeast winds. Freezing levels at valley bottom. Alpine high of -20. 

MONDAY: Mostly sunny, moderate wind from the northeast. Freezing levels below valley bottom, alpine high of -20. Chance of isolated flurries. 

TUESDAY: Mostly clear, moderate northeast winds. Freezing levels below valley bottom. Alpine high of -20. 

Avalanche Summary

Avalanche activity over the past few days has been limited to small slabs and loose avalanches in steep alpine terrain. 

With the incoming storm we expect to see natural and human triggered avalanche activity increase. 

Snowpack Summary

Up to 40 cm of new snow by Sunday afternoon will form reactive storm slabs at all elevations. The storm snow will bury a melt freeze crust on solar aspects at all elevations, and wind affected surfaces in exposed terrain. 

A buried surface hoar layer can be found 30-60 cm deep on north-facing slopes around treeline. This layer has been reactive in snowpack tests, and new snow is expected to increase the likelihood of triggering this layer. 

The snowpack below is well consolidated, with a crust/facet layer found near the bottom of the snowpack. It is currently considered dormant, but could become active later this season. Check out the forecaster blog for more information. 

Terrain and Travel

  • Avoid all avalanche terrain during periods of heavy snowfall.
  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

Large and reactive storm slabs will build overnight and into Sunday. Expect deeper deposits in wind affected areas - around ridgelines and on easterly facing slopes. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Valid until: Feb 20th, 2022 4:00PM