Avalanche Forecast

Archived

Apr 21st, 2024–Apr 22nd, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Regions

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

Wintery conditions continue through Monday. The following days will gradually be warming up with sun and less overnight freezes. WATCH OUT if the sun pokes out increasing trigger-ability particularly on steep solar aspects.

Confidence

Moderate

Avalanche Summary

Sunday's Maligne-Bald Hills patrol noted no new avalanches but visibility was limited to below mountain tops. No patrol occurred to the Icefields' area.

Snowpack Summary

Up to 10cm of snow with variable wind effect overlies a strong mid-pack above 2400m on shaded aspects. Sunny aspects, and everywhere below 2400m, starts in the morning as a supportive surface crust that breaks down with solar input and rising daytime temperatures.

Weather Summary

Mountain Weather Forecast is available at Avalanche Canada

Sunday night will be clear, flurries, -7 °C, and light gusting moderate West winds. Monday is forecasted to be sun, cloud, -2 °C, light winds, and 2100m freezing level. The prediction for Tuesday will be similar to Monday except -7 °C to 0 °C, light winds, and 2300m freezing level. Wednesday will bring 2400m freezing level and isolated flurries.

Terrain and Travel Advice

Avoid steep slopes when air temperatures are warm, or solar radiation is strong.
Minimize your exposure time below cornices.

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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

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.