Avalanche Forecast

Archived

Mar 11th, 2019–Mar 12th, 2019

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 unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Kananaskis.

Heads Up!!!! New wind slabs in the alpine and at tree line.

Confidence

High -

Weather Forecast

Tuesday will bring light flurries and strong SW winds in the morning with winds diminishing and snow developing after lunch. Snow amounts are expected to be12cm with a high temperature of -5c.

Avalanche Summary

Few new slab avalanches were observed on SW to NE faces .

Snowpack Summary

Widespread wind slab in the alpine and treeline from the strong SW winds over the last 24hours. Time for heads up for lee and cross loaded features that have experienced substantial wind loading The formerly strong midpack has been decimated by a month of cold weather and is now highly variable in its density, with many areas exhibiting no structure at all. Much of the region's snowpack consists of recent wind slabs sitting on up to 80cm of depth hoar and facets. It will be interesting to see how the snowpack adjusts to the recent load and the forecasted warm temperatures. It is likely that full-depth avalanches will become more commonplace in the next few days.

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.