Avalanche Forecast

Issued: Apr 4th, 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, Cornices and Loose Wet.

Avalanche Canada rbuhler, Avalanche Canada

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The recent storm snow is expected to be touchy on Tuesday and human-triggered avalanches are likely. 

Depending on the timing and amount of sun, solar-triggered avalanches are also possible. Extra caution is recommended around steep, sun-exposed slopes. 

Summary

Confidence

Low - Uncertainty is due to the limited number of field observations. Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.

Weather Forecast

Unsettled conditions are expected for Tuesday as the storm system exits the region and a ridge of high pressure begins to build in its wake. 

Monday Night: Snowfall 10-30 cm, strong to extreme SW wind, freezing level low around 800 m. 

Tuesday: A mix of sun and cloud with lingering flurries in the morning, strong NW wind easing through the day, freezing level high around 1200 m.

Wednesday: A mix of sun and cloud, moderate to strong SW wind, freezing level high around 1500 m.

Thursday: Mainly cloudy with a chance of sunny breaks, moderate to strong SW wind, freezing level high 2000-2500 m.

Avalanche Summary

On Sunday, numerous natural and skier-triggered size 1 storm slabs were reported on northwest through northeast aspects at treeline. These were 10-20 cm thick and sliding on a melt-freeze crust. This MIN post reported a small natural avalanche as well as a remotely triggered wind slab avalanche which was 30 cm thick and sliding on the crust. This MIN post describes a small natural avalanche on a northeast aspect at 1100 m elevation. 

Observations are very limited this time of year. If you are getting out in the backcountry, please consider sharing your observations to the Mountain Information Network

Snowpack Summary

As of Monday afternoon, recent storm snow accumulation is estimated to be in the 50-80 cm range. This storm snow has buried a widespread, supportive melt-freeze crust. Strong to extreme southwest wind has redistributed this storm snow in exposed, high elevation terrain forming touchy wind slabs. 

The middle and lower snowpack are generally strong and well bonded.

Terrain and Travel

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Be aware of the potential for large avalanches due to the presence of a buried crust.
  • Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
  • Cornices become weak with daytime heating or solar exposure.

Problems

Storm Slabs

An icon showing Storm Slabs

The recent storm snow is expected to be touchy on Tuesday, especially in wind exposed terrain. 

If the sun is out for extended periods, solar-triggered storm slabs are likely. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Cornices

An icon showing Cornices

Cornices are expected to have grown large during the recent storm and may be fragile on Tuesday, especially with extended exposure to the sun. Falling cornices are a likely trigger for slab avalanches on the slopes below. 

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Loose Wet

An icon showing Loose Wet

Loose wet avalanches should be expected from steep, sun-exposed slopes during the heat of the afternoon if the sun is out for extended periods. 

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 5th, 2022 4:00PM