Avalanche Forecast

Archived

Mar 17th, 2023–Mar 18th, 2023

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

Lizard-Flathead, Akamina, Flathead, Lizard.

Avalanche Danger will increase as the temperature rises through the day and the sun impacts slopes facing the sun.

Confidence

High

Avalanche Summary

Several large (size 2) natural slab avalanches were reported near Fernie on Thursday. The group observed the avalanches release when the sun hit open alpine slopes.

If you head out in the backcountry, let us know what you are seeing by submitting a report to the Mountain Information Network.

Snowpack Summary

20-40 cm of dense, wind-affected storm snow falling earlier in the week in the alpine tapers to a rain crust below 1400 m. This storm snow may sit on a sun crust on solar slopes and small surface hoar in sheltered, shaded areas.

The mid-snowpack is generally well-settled. The lower snowpack includes a layer of weak sugary crystals near the ground. This layer has not produced recent avalanche activity.

Weather Summary

Friday Night

Mainly clear. Treeline temperature -9 °C. Wind light southwest. Freezing level at valley bottom.

Saturday

Mainly sunny with cloudy periods. Treeline temperature -2 °C. Wind light southwest. Freezing level rising to1800-2000m.

Sunday

Mix of sun and cloud. Treeline temperature -1 °C. Wind light southwest. Freezing level rising to 2000m.

Monday

Mainly cloudy with scattered flurries. Treeline temperature -4 °C. Wind light east. Freezing level 1400m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be especially cautious as you transition into wind affected terrain.
Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
Pay attention to cornices and give them a wide berth when traveling on or below ridges.

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.

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.