Avalanche Forecast

Archived

Nov 27th, 2024–Nov 29th, 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

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

Winds are expected to pick up the next few days which will likely create new wind slabs in lee features. Avalanche and riding conditions will depend largely on what the wind does. Our neighbors to the south have been seeing avalanches on the October crust, so its a good time to stay vigilant.

Confidence

Moderate

Avalanche Summary

Several loose dry avalanches were observed beside the highway on Friday.

Ski hills to the south of the park have observed several natural and explosive triggered avalanches up to size 2 on the October crust at the bottom of the snowpack.

Snowpack Summary

10-15 cm of of recent storm snow sits on old windslabs and a faceted midpack. There is a thin crust 20-30cm below the surface, as well as a notable 5-15 cm thick crust from October near the base of the snowpack, surrounded by facets above and below. There is a lot of uncertainty about what it will take to trigger this layer.

Snow depth at Treeline is approximately 70 cm tapering off rapidly below. In the Alpine there is around 80 cm with variability due to wind redistributing the snow

Weather Summary

Thursday

4cm of new snow expected. Mainly cloudy with scattered flurries. Alpine temperature: Low -13 °C, High -10 °C. Ridge winds from the southwest: 10-30 km/h.

Friday

Cloudy with sunny periods and isolated flurries. Trace precipitation. Alpine temperature: Low -14 °C, High -11 °C. 15-35 km/h ridgetop winds out of the southwest

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.

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.