Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Apr 5th, 2022–Apr 6th, 2022

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

Purcells.

Keep an eye on the snow surface, as it becomes moist from solar input the size and likelihood of avalanches will increase.

Confidence

Moderate - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

Tuesday night: possibility of light flurries bringing trace amounts of new snow. Light west winds and a low of -9 at 2000 m.

Wednesday: Sunny with no new snow expected. Light west winds and freezing levels around 1900 m.

Thursday: Sunny with no new snow expected. Moderate southwest winds and freezing levels rising to 2500 m in the south and 2100 m in the north of the range.

Friday: Stormy with rain at lower elevations and up to 5 cm of new snow ain the alpine. Moderate to strong southwest winds. Freezing level around 2300 m.

Avalanche Summary

On Monday ski cutting produced size one wind slab avalanches in steep terrain. Several size one natural dry loose avalanches were also observed in steep unskiable terrain. In the western part of the range several natural wind slab avalanches to size two were observed.

Snowpack Summary

Wind slabs exist in exposed terrain in the treeline and alpine on north and east aspects. A crust exists on or near the surface on all aspects as high as 2500 m. This crust will become moist at lower elevations and to mountain top on sun exposed slopes as the freezing level rises and the sun comes out. 

A thick rain crust with facets above from early December is buried around 150 cm deep. Large avalanches were naturally triggered on this layer during the last significant warming event in western terrain near the Bugaboos. Significant solar input and warming could wake this layer up again.

Terrain and Travel

  • Avoid sun exposed slopes, especially if snow surface is moist or wet.
  • Avoid exposure to slopes that have cornices overhead.
  • Wind slabs may be poorly bonded to the underlying crust.

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.

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.

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.