Avalanche Forecast

Issued: Feb 13th, 2017 3:08PM

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

michael.olsthoorn, Alberta Parks

Kananaskis.

Hazard may increase to HIGH with daytime heating and solar radiation. Conservative route selection and staying away from overhead exposure is advised.

Summary

Confidence

Moderate -

Weather Forecast

A ridge of high pressure will bring warmer temps and higher freezing levels for next few days. For Tuesday, forecast shows a high of 0 deg in the Alpine with freezing level at 2100m and winds SW at 25km/hr. Even warmer temperatures are forecast for Wednesday. Stay tuned.

Avalanche Summary

No new activity was observed today but all the slopes in the back country do look primed for avalanching.

Snowpack Summary

Wind slabs dominate the Alpine and Treeline elevation bands. These slabs are found on all aspects, but the most recent loading pattern is from the SW loading up traditional lee and cross-loaded terrain and starting to strip windward slopes in the Alpine. Cornices have grown to a significant size and can be triggered by the forecast warmer temperatures, Below Treeline , rapid settlement of the snowpack was observed with the warmer temperatures. Whumphing is widespread and can propagate a long ways through the weaker layers. Think of this as you approach overhead terrain. Moist snow can be expected at lower elevations and on steep solar aspects.

Problems

Wind Slabs

Wind slabs are everywhere, but the most recent loading is onto typical lee and cross-loaded features. The slabs are 50-60cm thick and are sitting on a variety of surfaces. These slabs are very sensitive to human-triggering.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Avoid freshly wind loaded features.Avoid cross loaded slopes at or above treeline.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

2 - 3

Cornices

Cornices are large and relatively new to the scene. Expect them to fail easily, especially as it warms up.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Very Likely

Expected Size

2 - 3

Deep Persistent Slabs

Many avalanches have stepped to this layer. Very large avalanches can be expected if this layer is involved. Large triggers(cornices) may wake this layer up.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 4

Valid until: Feb 14th, 2017 2:00PM