Avalanche Forecast

Archived

Jan 25th, 2024–Jan 26th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

So far the warm weather is helping the upper layers settle and become less reactive. But remember, this could change quickly with sun exposure, or warmer than predicted weather.

Confidence

Moderate

Avalanche Summary

Nothing new has been reported or observed.

Snowpack Summary

The top 30cm of the snowpack is either made up of settled snow or wind slab and is overlying 5-15cm of facets. These wind slabs were found at treeline and above and produced some cracking when travelling uphill. The January 8th facet/crust surface hoar layer is down about 25-30cm and is getting better as the warmth sinks in. Having said that, there was some whumphing today in flat areas below treeline. There's a 20cm thick layer of facets beneath the Jan 8th interface that we think is the culprit for the cracking/whumphing and recent avalanches. Deeper yet, we still have the well behaved Dec 5th crust hanging in there.

Weather Summary

Is it April already? Another warm day tomorrow, expect a forecasted high of -4, but also expect that to off a bit. Freezing levels have crept up to almost 1900m lately. Flurries might give us a few centimeters at most. Winds? Light, but gusty from the SW all day.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Be carefull around freshly wind loaded features.
In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.