Archived

Avalanche Forecast

Apr 7th, 2019–Apr 8th, 2019

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Jasper.

A winter snowpack still exists at upper elevations. Be diligent in your hazard management as you transition into the alpine.

Weather Forecast

A brief bout of stable weather on Monday, ahead of a Coastal low pushing a series of fronts inland. Snow/rainfall starting Monday night is forecast to bring 10-25mm by the end of the week. Monday: Mainly sunny with cloudy periods and isolated flurries. Treeline temps: Low -8 C, High -2 C. Ridge wind light west. Freezing level: 2100m.

Snowpack Summary

Recent small snowfalls are settling quickly, over a melt-freeze crust everywhere except N aspects above treeline. Small windslabs can be found on lee slopes (alpine and treeline). It's still a winter snowpack on high North aspects, with facets in isolated areas giving sudden test results down 50cm, and whumphing in the South of the region.

Avalanche Summary

On Friday, a recent Large (Size 2.5), natural Persistent Slab was noted on a steep NE facing alpine slope in the Icefields area. Previous persistent slab activity was noted on N & NE aspects above 2700m on Mt Wilson.

Confidence

Avalanche Problems

Wind Slabs

Pockets of windslab continue to build in alpine lees. With moderate-strong SW winds Saturday night into Sunday, this problem may now extend down to treeline.

Choose terrain that offers options, so you can avoid visible Wind Slabs.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

Natural avalanche activity, whumphing and test results indicate that a weak layer of facets buried 50cm down is persisting in some areas. This is more prevalent at the Columbia Icefields & South.

Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1.5 - 2.5