Avalanche Forecast

Issued: Apr 16th, 2018 3:00PM

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

michael.olsthoorn, Alberta Parks

Kananaskis.

Challenging avalanche conditions with poor ski quality.

Summary

Confidence

Weather Forecast

Tuesday will be a typical spring day with sunny periods, cloudy periods and isolated flurries. Winds will be 35-50km/h from the west with a freezing level of 2000m.

Avalanche Summary

Numerous avalanches were observed that had occurred on Sunday in the late afternoon. Some of these avalanches were loose and wet and others were slabs with distinctive crown lines of approximately 50cm deep on average.

Snowpack Summary

Today, we tried to ski the Hero's knob loop and turned around due to a slab sitting on the April 13 crust and the exposure to natural avalanches. 10cm new snow from Sunday night is sitting on a thin melt /freeze crust. Below this is a 40-50cm slab that is poorly bonded to another melt/freeze crust that is 5cm thick produced on April 13 and extends into the alpine. This slab has produced numerous natural avalanches at tree line and in the alpine on all aspects. It is very likely that more avalanches will occur on this layer with strong solar radiation. It is recommended to approach tree line and the alpine with caution and give time for this slab to heal.Â The ski quality was poor below 2200m.

Problems

Storm Slabs

40-50cm slab poorly bonded to the April 13 melt/freeze crust interface.

Watch for signs of instability such as whumpfing, or cracking. Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Loose Wet

Keep an eye out for rapidly increasing solar radiation.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Use extra caution on slopes if the snow is moist or wet.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Cornices

Keep a safe distance from overhead cornices.

Cornices become weak with daytime heating, so travel early on exposed slopes.Pay attention to overhead hazards like cornices which could easily trigger persistent slabs.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Apr 17th, 2018 2:00PM