Avalanche Forecast

Issued: Feb 6th, 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.

jasper snow safety, Parks Canada

Jasper.

Human triggering remains a possibility. Assess the stability before committing to avalanche terrain.

Summary

Weather Forecast

Thursday will be mainly cloudy with isolated flurries, trace snow, alpine temperature high -15 C, and 10km/hr west ridge winds. Friday will be cloudy with sunny periods and isolated flurries, alpine temperatures Low -31 C and High -16 C, and light East ridge winds. A detailed mountain weather forecast is available from Avalanche Canada.

Snowpack Summary

50cm from Feb 2nd was followed by strong Northerly winds. This snow overloaded; the Jan 18 persistent weaknesses such as surface hoar 10mm in sheltered areas at lower elevations, crust on steep solar slopes, and facets on Northerly alpine slopes; and the deep persistent basal facet and depth hoar weakness - particularly in shallow snowpack areas.

Avalanche Summary

Feb 4th avalanche control work at the Icefields produced several large size 2-2.5 persistent and deep persistent slab avalanches. A natural cycle of large slab avalanches occurred during this last storm but activity has tapered off.Help forecast - share observations HERE, on the Mountain Information Network!

Confidence

Due to the number and quality of field observations

Problems

Persistent Slabs

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

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

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.

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

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 7th, 2019 4:00PM