Avalanche Forecast

Issued: Mar 3rd, 2013 8:32AM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Very touchy avalanche conditions currently exist and a natural avalanche cycle is occurring. Be very conservative in your terrain choices.

Summary

Confidence

Good

Weather Forecast

Another 5cm+ are possible before the storm finally peters out late Sunday night. Monday will bring a mix of sun and cloud with occasional light flurries. Winds will be light and temperatures could drop to -18 in the alpine.

Avalanche Summary

Visibility was extremely limited today, but field teams did observe a size 2.0 naturally triggered avalanche on an E aspect on Mt. Rundle while inspecting HWY 742 this morning. It was too obscure to identify the start zone elevation of this slide, but it did run full path. HWY 742 remains closed from the Mt. Shark Road to the Grassi Lakes Trailhead pending avalanche control work on Monday. Estimated time of re-opening is late Monday afternoon with low confidence.

Snowpack Summary

15 to 20cm of snow in the past 24hrs, with storm snow totals now near 50 to 60cm. Extensive storm slab development continues in alpine and treeline areas. Slabs are very sensitive to human triggering and a natural avalanche cycle is occurring.

Problems

Storm Slabs

An additional 15 to 20cm in the past 24hrs has added to the already 50cm of storm snow. Slab development is extensive in lee and cross-loaded terrain. Prime conditions exist for human triggering and a natural avalanche cycle is occurring.

Avoid all avalanche terrain.>Avoid exposure to overhead avalanche terrain, as large avalanches may reach the end of runout zones.>

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely - Certain

Expected Size

2 - 5

Cornices

Cornices have grown significantly in the past 72hrs and several cornice failures occurred yesterday which triggered slab avalanches on the slopes below.

Pay attention to overhead hazards like cornices.>Avoid exposure to overhead avalanche terrain, as large avalanches may reach the end of runout zones.>

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

2 - 5

Loose Dry

Recent snowfall and moderate winds has lead to sluffing from steep terrain on all aspects at all elevations.

Be cautious of sluffing in steep terrain.>Avoid travelling on ledges and cliffs where sluffing may have severe consequences.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Valid until: Mar 4th, 2013 2:00PM