Avalanche Forecast

Archived

Feb 17th, 2025–Feb 19th, 2025

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

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Good skiing exists in areas that have been sheltered from the wind.

Assess wind loading on open slopes before committing to terrain as windslabs may remain reactive to human triggers.

Confidence

High

Avalanche Summary

Numerous Loose dry avalanches and one cornice fall that did not produce a slab were observed on steep solar aspects on the 17th.

There was a size 1 wind slab skier accidental reported on the back side of Parkers Ridge on the 14th. Check out the MIN on the main map for more information.

Marmot Basin was able to produce a size 2 cornice triggered avalanche with explosives on the 14th where the cornice chunks entrained loose dry snow.

Snowpack Summary

In the alpine and treeline there has been widespread wind affect. In sheltered areas there is roughly 15cm of snow overlying the January 30th layer which is a temperature crust or wind slab depending on the area.

The midpack is weak and faceted. At the bottom of the snowpack the early season crusts are faceting and breaking down but continue to persist along with large depth hoar. The snowpack at tree line is 70-130 cm in the Icefields area and 50 cm in the Maligne area.

Weather Summary

Tuesday

A mix of sun and cloud.

Precipitation: Nil.

Alpine temperature: High -12 °C.

Light ridge wind.

Wednesday

Cloudy with sunny periods.

Precipitation: Nil.

Alpine temperature: Low -17 °C, High -8 °C.

Ridge wind southwest: 10 km/h.

Thursday

Cloudy with sunny periods and isolated flurries.

Precipitation: Trace.

Alpine temperature: Low -9 °C, High -7 °C.

Ridge wind west: 15-25 km/h.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

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.