Avalanche Forecast

Issued: Apr 10th, 2012 4:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

With little to no freeze expected overnight and freezing levels near 3600m on Wednesday, avalanche danger will climb rapidly and could hit HIGH on steep solar aspects. Avalanche control on EEOR and Mt. Buller planned for Wednesday at 11:00am

Summary

Confidence

Good

Weather Forecast

Freezing levels will stay elevated through the night and spike again on Wednesday to at least 3400m. It is quite possible that there will not be a significant overnight freeze. Winds are expected to be light from the south and temperatures at 3000m will reach +5.

Avalanche Summary

Widespread solar triggered sluffing occurred through the day up to size 2.5, beginning on SE aspects and progressing to S and W aspects. Several large slab avalanches occurred in the alpine on southerly slopes. These slides were in the range of size 2.5 and 3.0, had fracture depths in excess of one meter and wide propagations.

Snowpack Summary

Crusts exist on all aspects at all elevations, except for true north aspects which have crusts below 2400m, and dry snow above. The snowpack is settling rapidly with the very warm temperatures. The deeply buried weak layers of surface hoar and basal facets are responsible for numerous large, destructive avalanches over the past few days. Cornices are large.

Problems

Loose Wet

Loose wet slides up to size 2.5 occurred today on solar aspects. These slides were gaining mass and running far in some cases. Pay close attention to terrain that is overhead as you travel and be aware of your regroup spots.

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

Elevations: All elevations.

Likelihood

Very Likely - Certain

Expected Size

1 - 4

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: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 7

Valid until: Apr 11th, 2012 9:00AM