Avalanche Forecast

Issued: Feb 5th, 2019 4:00PM

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

jonas hoke, Parks Canada

Jasper.

Human triggering of recently overloaded weaknesses remains a possibility, assess the local snowpack before committing to avalanche terrain.

Summary

Weather Forecast

An upper level NW flow has brought "warmer" air and some cloud cover to the region. A low pressure center sliding down the coast later in the week will bring light precip Thursday.Weds: Sunny with cloudy periods. Alpine temperature: Low -23 C, High -15 C. Ridge wind light NW.A detailed mountain weather forecast is available from Avalanche Canada.

Snowpack Summary

50cm recent storm snow was followed by strong Northerly winds. This storm snow overloaded the Jan 18 persistent weakness (srfce hoar up to 10mm in sheltered areas at lower elevations, crust on steep solar slopes, and facets on Northerly alpine slopes), and the deep persistent weakness (basal facets - found predominantly in shallow snowpack areas).

Avalanche Summary

Avalanche control work Monday between the Icefields and Saskatchewan crossing, produced several large (size 2-2.5) persistent and deep persistent slab avalanches.A natural cycle of large slab avalanches occurred during the most recent storm.Help forecast - share observations HERE, on the Mountain Information Network!

Confidence

Problems

Persistent Slabs

Up to 50cm of recent snow followed by strong winds has built thick slabs well into the terrain.

Carefully assess open slopes at and below treeline where buried surface hoar may be preserved.The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

Deep Persistent Slabs

New snow with strong winds recently overloaded the deep persistent weakness in shallow snowpack areas.

Be cautious in shallow snowpack areas where triggering is more likely.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3.5

Loose Dry

Expect sluffing out of steep rocky terrain if the sun is on it.

Be cautious with gully features.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Feb 6th, 2019 4:00PM