Avalanche Forecast

Issued: Apr 11th, 2012 4:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

Weather models are calling for freezing levels to slowly drop but if the moisture comes before the cooling trend and rain falls, avalanche danger will be higher than forecast. Its spring, and stability will decrease as the day warms up. Start EARLY

Summary

Confidence

Fair - Freezing levels are uncertain on Thursday

Weather Forecast

Temps will begin to cool over the next few days as an upslope pattern begins to set up as a low develops in central Alberta. Winds will become northerly and 6-10mm of precip may fall over the next 24hrs. If temps remain warmer than forecast some of this precip may fall initially as rain and cause the avalanche danger to rise higher than forecasted. Pay close attention to freezing levels and precipitation type.

Avalanche Summary

Control run on EEOR and on the Buller Corner area. No results bigger than size 2. Warm temps continue to produce numerous loose wet avalanches up to size 1 on all aspects except for true north.

Snowpack Summary

Melt freeze crust on all aspects but true north up to 3500m. This crust was breaking down between 10-11am each day. On North aspects above 2400m dry powder snow can still be found. No sheers noted in the upper snowpack.

Problems

Loose Wet

Loose wet slides up to size 1.5 occurred wednesday on solar aspects. The intense spring-time sunshine does not take much time to change the snow stability. If some of the forecast precip falls as rain, we can expect stability to rapidly degrade.

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

Elevations: All elevations.

Likelihood

Very Likely - Certain

Expected Size

1 - 4

Cornices

Cornice failures are becoming more common as temperatures warm up. Pay close attention to whats overhead or affecting your planned trip. The sun hits the peaks way earlier than the valley floor.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 3

Persistent Slabs

The Feb surface hoar and basal facets are a concern in the snowpack. Solar radiation and large loads, such as cornices, have triggered avalanches up to size 3.5 recently. The spring transition could see more slides stepping down to these layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 7

Valid until: Apr 12th, 2012 9:00AM