Avalanche Forecast

FRIDAY NIGHT - Mainly clear / moderate to strong southwest wind / alpine low temperature near -1 / freezing level 2500 m, dropping to 2000 m

SATURDAY - Mainly cloudy / moderate to strong southwest wind / alpine high temperature near -1 / freezing level 2000 m, dropping to 1500 m in the afternoon and to valley bottom overnight

SUNDAY - Cloudy with sunny periods and isolated flurries / moderate to strong southwest wind / alpine high temperature near -5 / freezing level 1500 m, dropping to valley bottom overnight 

MONDAY - A mix of sun and cloud / moderate west wind / alpine high temperature near -6 / freezing level 1500 m, dropping to valley bottom overnight

There is a lot of uncertainty with regard to how quickly temperatures will drop on Saturday, and how the persistent weak layers will respond to the cooling trend. Though often less of a concern than rapid warming, cooling in the wake of warm temperatures can also trigger a spike in avalanche activity. 

On Thursday, there were several reports of natural and human-triggered wet loose avalanches up to size 1.5. There was also a few size 2 solar triggered wind slab avalanches reported on south to southeast aspects. In addition, there were three size 2.5 natural persistent slab avalanches reported in the nearby Waterton National Park region.

There were a few size 1 natural and human-triggered wet loose avalanches reported on solar aspects on Wednesday. There were also reports of several size 2-2.5 natural wet loose avalanches in the neighbouring Waterton National Park region, and two size 2.5 natural persistent slab avalanches in the neighbouring Kananaskis Country region.

Warm temperatures and sunshine have made the snow surface moist in most areas. Dry snow may still be found on north aspects. This moist snow will change into a crust when temperatures finally dip back below zero. Wind slabs are likely still present on north to east aspects in the alpine and at treeline. Upper elevations have been scoured down to rocks or crusts in many areas due to recent strong southwest winds. 

40-60 cm (in some places up to 100 cm) of snow sits above a persistent weak layer of facets that was buried in mid-February. Recent snowpack tests indicate that this layer is reactive and has the potential to propagate widely, causing large avalanches. 

There is another persistent weak layer that was buried at the end of January. This layer consists of surface hoar, facets, and/or a hard melt-freeze crust. recent MIN reports show that these layers remain easily triggered by people. 

Weak faceted snow and a decomposing melt-freeze crust can be found near the base of the snowpack. 

• Minimize overhead exposure; avalanches triggered by warming or cornice fall may be large and destructive.
• A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
• Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
• The trees are not the safe-haven they normally are at this time. Terrain at treeline is primed for human triggered avalanches.