Avalanche Forecast

Issued: Apr 7th, 2019 4:00PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs and Persistent Slabs.

jonas hoke, Parks Canada

Jasper.

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

Summary

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

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

Valid until: Apr 8th, 2019 4:00PM