Avalanche Forecast

Issued: May 9th, 2019 4:31PM

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

Parks Canada jesse milner, Parks Canada

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Buckle up ladies and gentlemen! The spring avalanche cycle has arrived!

Summary

Weather Forecast

Warm with no overnight freezes.

Friday: Sunny with cloudy periods. Alpine temps around 9. Light north winds. Freezing levels 2900m.

Saturday: Sunny with cloudy periods. Alpine temps: Low 5, High 13. Light west winds. Freezing levels 3600m.

Sunday: A change in weather with high freezing levels (2800m or so) and rain starting in the afternoon (5mm)

Snowpack Summary

Snowpack is becoming isothermal into the alpine on shady aspects. The snowpack has transitioned rapidly from Winter to a summer like snowpack. Little to no overnight freezes are expected.

Avalanche Summary

The past 3 days there has been an avalanche cycle with the warming trend. Numerous loose wet avalanches up to size 2 have been observed in the alpine and treeline. Near Jasper in shallow snowpack areas townsite several large (size 3) slab avalanches have been observed on North to Easterly aspects in the alpine and running into valley bottoms. 

Confidence

Problems

Loose Wet

An icon showing Loose Wet

Summer like temps have created an avalanche cycle. With no overnight freezes and more sunny days forecasted this problem will continue for the next while.

  • If triggered loose wet sluffs may step down to deeper layers resulting in larger avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Weak mid-pack facets and upper-snowpack are reactive, especially on shaded, wind-sheltered slopes. This is a Wet Slab problem on solar aspects, as water accumulates above strong crusts.

  • Minimize exposure to big slopes, especially during the heat of the day.
  • If off-trail travel is deep and punchy, avoid all avalanche terrain, including runouts.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 3

Cornices

An icon showing Cornices

Occasional cornice falls are expected, increasing into the weekend. some of these may trigger large slab avalanches, running well down into lower elevations.

  • Stay well to the windward side of corniced ridges.
  • Minimize exposure to overhead hazard from cornices.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: May 10th, 2019 4:00PM