Avalanche Forecast

Issued: Dec 3rd, 2012 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

25cm of new snow overnight at treeline and up to 50cm over the last 4 days. LOTS of snow is available for transport. If the forecast extreme SW winds occur on Tuesday, there will be a spike in Avalanche Danger.

Summary

Confidence

Fair - Wind speed or direction are uncertain on Tuesday

Weather Forecast

Light flurries expected Tuesday bringing up to 10cm of snow. A severe spike in the high altitude winds are forecast which will shift to the SW and reach 125km/h. Alpine temperatures will be near -5 with a significant cooling trend to begin on Wednesday.

Avalanche Summary

Several loose naturally triggered avalanches were heard but not seen today. Estimate the sizes were between 1.0 and 2.0. Possibly some were triggered by cornice collapses and all originated in steep N and E aspects in the Alpine.

Snowpack Summary

25 of new snow overnight with storm snow totals up to 50cm from the last 4 days. Storm slab formation is extensive in the alpine, but is highly variable at treeline.

Problems

Storm Slabs

25cm of new snow overnight with storm snow totals near 50cm. Storm slab formation is ongoing in the Alpine and isolated areas at Treeline. The storm slabs are becoming easier to trigger, particularly in the Alpine.

Be cautious as you transition into wind affected terrain.>Avoid lee and cross-loaded terrain near ridge crests.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 5

Loose Dry

Loose dry avalanches from steep unskiable terrain on all aspects, but more prominent on lee aspects.

Pay attention to overhead hazards like cornices.>Avoid travelling under cliffs that are exposed to sluffing from above.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Persistent Slabs

The Nov rain crust persists about 30cm off the ground throughout the forecast area and is reactive to stability tests in the hard range. Avalanches in the upper snowpack may step down to this weakness.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Be aware of thin areas that may propagate to deeper instabilites.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Dec 4th, 2012 2:00PM