Avalanche Forecast

Archived

Mar 12th, 2021–Mar 13th, 2021

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.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Kananaskis.

Given the rapid softening of the snow with the sun exposure, the aspect and timing game becomes critical. Make sure to avoid solar slopes by mid morning, and seek out those north aspects for the driest snow. The ratings will worsen locally with sun exposure.

Confidence

High -

Weather Forecast

If you haven't already, find a bottle of sun screen and put a healthy coat on. The sun is strong, and luckily we'll be seeing a lot of it in the next while. Tomorrow will have some cloud, but not enough to keep it cool. The daytime high is +4 with a freezing level of almost 2300m. No snow and light winds will top off the forecast. And remember, SPF 60 as a minimum!

Avalanche Summary

Nothing new today, but observations were limited.

Snowpack Summary

It is sure feeling Springlike out there but there is still a few things happening in the snowpack. On solar aspects, expect to find a crust in the early morning hours and then turn to moist snow later on. The sun has a lot of punch now so choose your route carefully in terms of overhead hazards like cornices and wet loose avalanches on southern aspects. The hazard is likely to go up during the day with the sun and moist snow. In other words, the day would start at Moderate and quickly change to Considerable with warming and solar radiation.

The forecasters found that there is still variability in the top 60cm of the snowpack. We mostly found several buried wind slabs down 15cm and 40cm overlying less dense layers. Good skiing and dry snow will still be found on North and NE aspects.

Terrain and Travel

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
Cornices become weak with daytime heating.
Avoid rock outcroppings, convexities, and anywhere the snowpack is thin and/or variable.
Be alert to conditions that change with elevation and sun exposure.

Problems

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.

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.