Avalanche Forecast

Archived

Feb 21st, 2024–Feb 22nd, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

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

A bit more wind has been experienced in the last 24hrs and forecasted moderate to strong winds Thursday will disturb more surface snow. Expect further wind slab development at upper elevations.

Confidence

High

Avalanche Summary

No new avalanches observed or reported.

Snowpack Summary

A few cm's of snow fell in the last 24hrs. Recent winds have created wind slabs at upper elevations. In protected areas as much as 20cm of low density snow overlies the Feb 3 crust. This crust layer is prominent on all aspects below 2400m and on solar aspects to at least 2600m. Recently formed surface sun crusts are also now found on solar aspects. The mid pack consists of a wide variety of crust and facet combinations, and the basal weak layers remain just that...weak.

Weather Summary

Thursday will be cloudy with very light flurries. Snow accumulations will be minimal (maybe 2cm). Temps should reach -4C with moderate to strong westerly winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid areas with a thin or variable snowpack.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Wind slabs may be poorly bonded to the underlying crust.

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.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.