Avalanche Forecast

Archived

Apr 18th, 2024–Apr 19th, 2024

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Regions

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

Variable wind loading on all aspects in the alpine.

Large cornices present. Seasonal coverage on all glaciers is both thin and weak. For a fleeting moment, avalanches are the least of your worries in the back-country.

Confidence

High

Avalanche Summary

No new avalanches were observed or reported.

Snowpack Summary

Convective spring storms have spread a trace, up to 10cm of new snow through the region. HN sits on a supportive snowpack to mountaintops on all aspects.

There's a strong midpack and dry snow above 2400m on shaded aspects. Solar aspects start as a supportive, hard surface crust that breaks down with strong sun and temps. BTL travel is quite variable but, almost always poor by early PM.

Weather Summary

Mountain Weather Forecast is available at Avalanche Canada

Thursday Evening

Clearing and cooling overnight. Alpine low -13 °C. Ridge winds Light. Freezing level valley bottom.

Friday

Sunny with cloudy periods. Alp High -4 °C. Ridge winds, light, easterly: Freezing level 1700m

Terrain and Travel Advice

Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.