Avalanche Forecast

Issued: Apr 11th, 2017 3:01PM

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

matt.mueller, Alberta Parks

Kananaskis.

Once again we are expecting an upslope storm to bring some snow. It will start tomorrow and carry on into Thursday. Remember that upslope storms have a tendency to reverse load slopes.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

Flurries with light winds overnight. We are expecting a stronger and more unsettled system to arrive by tomorrow afternoon bringing almost 10cm of new snow. SE winds will be a bit stronger as this storm plays out. On average 20 km/hr with gusts up to 45 in exposed areas. The alpine high will reach -4. Freezing level 2000m.

Avalanche Summary

Only small loose dry avalanches were noted today in steep alpine terrain.

Snowpack Summary

No significant new snow last night, only a light dusting in the southern part of the forecast region. Cold dry snow still exists in the high alpine and northern aspects. A significant melt freeze crust is on all aspects up to 2300m, and higher on solar aspects. The cloud cover and cooler temps today helped keep the crust frozen and supportive everywhere except for the valley bottoms. Moist snow by mid afternoon. Tests today revealed no significant shears at treeline elevations, however expect to still find the Dec facets near the bottom of the snow and potentially reactive to human triggering in thin areas.

Problems

Wind Slabs

A variety of slabs, new and old, remain in the upper snowpack. With the new snow coming, expect thin storm slabs to develop and potentially react with the deeper windslabs. There is an upslope component to this storm, so expect some reverse loading.

Keep an eye out for reverse loading created by an upslope storm.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

Loading on this layer continues as the flurries and squalls pass through. Alpine areas that have not seen the warmth yet are the most suspect.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Apr 12th, 2017 2:00PM