Avalanche Forecast

Issued: Feb 12th, 2023 4:00PM

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

Avalanche Canada GL, Avalanche Canada

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There is a storm warning for Jasper Sunday night but the amounts are expected to be less in the Maligne area; however, the snowpack is inherently weak and untrustworthy. We expect the avalanche hazard to rise with the incoming weather system.

Summary

Confidence

Moderate

Avalanche Summary

Sunday's Icefield patrol was very poor visibility. A size 2.5 deep persistent slab just south of Marmot, as well as a couple wind slabs up to size 2 in the Churchill Slide Paths area, were observed from 93N on Saturday.

Don't forget to post avalanche observations to the MIN.

Snowpack Summary

10cm of new snow over the last few days has been redistributed by strong SW winds, creating wind slabs in the alpine and into exposed tree line. A weak melt freeze crust facet combo down 25cm below 2100m is showing sudden collapse results in snow pit tests. Generally, the bottom of the snowpack is weak facets and depth hoar.

Weather Summary

A snowfall warning has been issued for Jasper with potentially 20cm or more with strong to extreme southwesterly winds. The snowfall will taper off Monday afternoon. Weather models are showing only 10cm for the Maligne area yet one should expect this amount to be exceeded.

Detailed weather forecasts from Avalanche Canada: https://www.avalanche.ca/weather/forecast

Terrain and Travel Advice

  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The incoming storm snow will test the inherently weak Facets and Depth Hoar near ground. Avalanches initiating in the upper snowpack are likely to step down to this layer and gain significant mass.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs

Strong to extreme winds can push the new snow further down the start zone than one would normally encounter. Watch for Sunday's storm increasing this problem into non-typical locations.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Storm Slabs

An icon showing Storm Slabs

Sunday night's storm may exceed forecasted amounts. If that happens, expect a storm slab condition particularly in alpine locations.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 2.5

Valid until: Feb 13th, 2023 4:00PM