Avalanche Forecast

Issued: Apr 16th, 2021 4:00PM

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

Avalanche Canada kdevine, Avalanche Canada

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Start (and finish) your day early and avoid exposure to sun-exposed avalanche terrain. Look for high elevation north facing objectives without cornices overhead, and plan your egress route carefully.

Check out the Forecaster's Blog for more on managing spring conditions.

Summary

Confidence

Moderate - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

A ridge of high pressure, with sunny skies and high freezing levels continues to dominate the weather pattern on Saturday. Sunday may bring a cooler, cloudier day.

Friday night - Clear / light east wind / alpine low temperature near 5 / freezing level 3100 m

Saturday - Sunny / light southwest wind / alpine high temperature near 8 / freezing level 3200 m 

Sunday - Sunny in the morning with increasing cloud throughout the day / moderate northeast wind / alpine high temperature near 5 / freezing level 3000 m, falling to 2300 m in the afternoon

Monday - Mainly sunny / light northeast wind / alpine high temperature near 3 / freezing level 2400 m

Avalanche Summary

There have been several natural wet loose and glide slab avalanches up to size 2.5 reported in recent days, as well as several natural cornice failures up to size 3.

Looking forward, wet loose avalanches and cornice failures are expected to continue with sun and warm temperatures. The likelihood and potential size of these increases when temperatures do not dip below freezing overnight, and avalanche activity will likely begin earlier in the day with each subsequent warm day.

Wind slabs may still be possible to trigger on high elevation north aspects.

Snowpack Summary

The snow surface may be a crust in some areas, but recent high overnight freezing levels may mean that the snow surface did not freeze in some places. Sunshine and warm temperatures are expected to quickly soften any crusts, resulting in a moist or wet snow surface.

Cornices are large and looming along ridgelines. Their release is unpredictable but increases in likelihood with daytime warming, requiring a large berth if you're travelling above or below them, especially when temperatures remain above zero overnight.

Terrain and Travel

  • The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
  • Avoid exposure to sunny slopes, especially in the afternoon.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Avoid areas with overhead hazard, especially solar aspects.
  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.

Problems

Loose Wet

An icon showing Loose Wet

The snow will quickly lose cohesion and become unstable with sun and warm temperatures.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Cornices

An icon showing Cornices

Cornices are large and looming along many ridgelines. They grow increasingly unstable during periods of warming.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 3

Valid until: Apr 17th, 2021 4:00PM