Avalanche Forecast

Issued: Apr 1st, 2018 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Happy Easter Everyone!

Summary

Weather Forecast

Weak fronts spinning off an Aleutian Low will push against the Arctic high that sits over Alberta. This will give a mix of sun and cloud with light flurries until later in the week. The overnight low for Monday will be -20, with the daytime high reaching -10. Winds will remain light and variable.

Snowpack Summary

A variety of slab conditions exist on most aspects at treeline and above. 10-20cm of recent storm snow has created a soft storm slab. This storm slab is up to 30cm thick . Below this, older slabs up to 60cm thick sit on a sun-crust on solar aspects and facets on polar aspects. Below treeline the snow is shallow.

Avalanche Summary

Explosives work on the Icefields Parkway produced numerous soft slab up to size 2.5.

Confidence

Problems

Storm Slabs

In most cases this interface presents as a manageable surface instability and is expected to go dormant pretty quickly. Pay close attention to any fellow travelers above and/or below you as enter fresh terrain.

Use caution on open slopes and convex rolls Be careful with wind loaded pockets while approaching and climbing ice routes.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Cornices

Cornices are growing with fresh snow additions. Several failures were noted, in most cases triggering a slab below.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3

Persistent Slabs

Wind slabs sit on a hard melt-freeze crust on solar aspects, and facets on polar aspects. Assess the bond at these interfaces carefully before committing to to a slope.

Avoid shallow snowpack areas where triggering is more likely.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Apr 2nd, 2018 4:00PM