Avalanche Forecast

Issued: Mar 9th, 2013 9:54AM

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

mike.koppang, Alberta Parks

Kananaskis.

Tomorrow will bring mixed skies, little precip and mild temperatures. Wind speeds are expected to pick up during the day. Solar radiation may be high, and should be watched throughout the day. Good skiing in shady areas right now. MM

Summary

Confidence

Good

Weather Forecast

Tomorrow will have more cloud than today, however solar radiation may still be a concern. The thickness of this cloud varies with the forecast. Alpine winds will pick up throughout Sunday and shift to a more westerly flow. No precip is expected.

Avalanche Summary

Of note was a widespread avalanche cycle that was centered in the Bow Valley but crept into the Goat Range in the Spray as well. Avalanches ran in the storm slabs and some stepped down to deeper layers as well. The common denominator was the high solar yesterday and cornice failure. Wide propagations made for large avalanches, up to sz3. Winds are picking up overnight tonight and aggressively redistributing the storm snow into new storm slabs.

Snowpack Summary

No new snow today. High solar radiation has taken a toll on any solar aspect up to TL elevations. Temperature crusts are widespread on any solar aspect at TL & below. In the ALP, windslabs were more reactive, but are expected to tighten up as the warm temps fade.

Problems

Storm Slabs

The recent storm snow continues to create soft slabs. Recent natural activity in the Bow Valley & Northern Spray clearly shows how touchy these slabs are. Up to sz3 avalanches were noted today.

Avoid areas with overhead hazard.>Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 5

Cornices

Ongoing winds are building cornices that are very touchy with solar heating. Numerous cornice and wind lip failures were noted today.

Avoid steep slopes below cornices.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 5

Wind Slabs

windslabs at treeline and above are still possible to trigger. Convex rolls in steep terrain below ridge crests and steep crossloaded gullies are concerning. Stepping to the Feb 14 PERSISTENT HARD SLAB was also observed today and remains a concern.

Avoid lee and cross-loaded terrain near ridge crests.>Avoid shallow snowpack areas where triggering is more likely.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Mar 10th, 2013 3:00PM