Avalanche Forecast

Issued: May 1st, 2019 4:21PM

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

Parks Canada jasper snow safety, Parks Canada

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Winter still exists in Jasper! Good skiing can be found in the right locations.

Summary

Weather Forecast

Cold and snowy for the next few days, Wednesday night around 10cm with light westerly winds with alpine temps around -4. Thursday flurries with an alpine high of -2 with around 5-10cm of accumulation with freezing levels up to 2100m. Friday flurries with alpine temps -5 moderate winds with strong gusts from the west with freezing levels at 1800m.

Snowpack Summary

5-15cm new low density snow overlies previous slabs built from N winds that may still be reactive in isolated alpine terrain where a crust is present. Buried facet layers remain a concern with small whumpfs and variable test results. Most concern is on protected northerly alpine features or where they sit on buried crusts.

Avalanche Summary

A team in the Columbia Icefields on wednesday did not observe any new avalanches. To the South of our region (Bow Summit), 2 large (size 2 - 2.5) persistent slabs were remotely triggered on alpine SW aspects Tuesday. On Sunday, 1 Large (size 2.5) Persistent slab was observed in the Maligne Range on an East aspect, in convex alpine terrain.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Friday

Problems

Persistent Slabs

An icon showing Persistent Slabs

The two main concerns for persistent slabs are: Recent slabs from northerly winds. Especially steep solar terrain where a prominent sun crust would be. Next the concern for a midpack facet weakness in sheltered upper treeline and alpine features.

  • Watch for signs of instability such as recent avalanche activity, and whumpfing/cracking underfoot.
  • Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: May 2nd, 2019 4:00PM