Avalanche Forecast

Archived

Dec 28th, 2024–Dec 29th, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

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.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Good skiing can be found in sheltered locations. Look out for wind slabs in immediate lees in steeper terrain.

Confidence

Moderate

Avalanche Summary

There was a size 1, and a size 2 wind slab observed on different features of Parkers ridge on December 27th.

Outside the park there have been recent reports of explosive results on the early season crusts producing avalanches up to size 2.5

Snowpack Summary

Strong to extreme winds have redistributed surface snow and scoured windward aspects. Sheltered locations may still hold 15cm of soft snow if winds did not get to it. In protected areas, a weak layer of 7mm Surface Hoar may be 10-30cm down. The mid pack is mostly made up of facets. At the bottom of the snowpack there are multiple early season crusts with facets above and below.

Weather Summary

SundayCloudy with sunny periods and isolated flurries. Precipitation: Trace. Alpine temperature: High -6 °C. Ridge wind light to 15 km/h. Freezing level at valley bottom.

Monday

Cloudy with sunny periods. Precipitation: Nil. Alpine temperature: Low -12 °C, High -8 °C. Light ridge wind. Freezing level at valley bottom.

Tuesday

Cloudy with sunny periods and isolated flurries. Precipitation: Trace. Alpine temperature: Low -13 °C, High -10 °C. Ridge wind southwest: 10-25 km/h. Freezing level at valley bottom.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

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.