Avalanche Forecast

Issued: Apr 7th, 2017 3:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

We are expecting a poor freeze overnight with light rain at lower elevations and some snow at the higher areas. Cornices are also drooping right now so give them a wide berth.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

Forecasts are calling for continue light snowfalls along the divide overnight so we may see up to 10cm of snow at higher elevations. Cloudy conditions are expected so we are forecasting a poor overnight freeze and as a result, stability will remain at the current considerable level. If the forecasted temps come true, we will see the danger decrease as the snowpack begins to re-freeze. If the sun comes out, watch for rapid decreases in stability related to solar radiation. These decreases will be most apparent on steep solar aspects.

Avalanche Summary

No new slab avalanche activity was observed but there were numerous loose wet slides up to sz 1.5.

Snowpack Summary

Rain continued on friday up to 2500m and continued light flurries above this elevation. There was a very minimal freeze overnight on thursday and as a result, the top 10-30cm of the snow is wet. Above 2300m there is a widespread crust on solar aspects up to 2600m. Northern aspects are still holding dry snow but we have certainly transitioned into the time wherein if you want dry snow, you must be on a true north aspect and high into the alpine. The windslabs seem to be only found in isolated alpine areas but we are still getting moderate sudden collapse sheers in the basal facets down 150-180cm. Pin wheeling was observed on all aspects up to 2500m so ski quality is taking a turn for the worse.

Problems

Loose Wet

A very minimal freeze is expected below 2500m over the next 24hrs. Light rain is also forecast for the lower elevations. Loose wet slides may trigger deeper slabs failing on the basal facets.

Use extra caution on solar slopes or if the snow is moist or wet.If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

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

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Deep Persistent Slabs

We know it sounds like a broken record, but this deep layer is still a threat in any avalanche terrain that has not yet had extensive previous avalanching. While there is a lower probability of triggering, the consequences are high.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.Be wary of slopes that did not previously avalanche.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Wind Slabs

Expect to encounter these slabs along ridgelines and in crossloaded features in Alpine terrain.

Avoid freshly wind loaded features.Use caution in lee areas. Recent wind loading has created wind slabs.Avoid cross loaded slopes at or above treeline.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 8th, 2017 2:00PM