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

Feb 25th, 2022–Feb 26th, 2022

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

Regions

Purcells.

Lingering wind slabs may still be reactive to human-triggering in exposed terrain at higher elevations. 

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

One more day under the influence of high pressure before the first in a series of storm systems moves inland on Sunday. 

Friday Night: Mainly clear, light NW wind, treeline low around -15 °C. 

Saturday: Mainly sunny, light to moderate SW wind, treeline high around -5 °C. 

Sunday: Mainly cloudy with flurries 2-4 cm, moderate to strong SW wind, treeline high around -4 °C. 

Monday: Snowfall, moderate to strong SW wind, treeline high around -2 °C. 

Avalanche Summary

On Thursday, a few natural wind slabs up to size 2.5 were observed in the alpine in the western part of the region. Explosive use triggered several size 2-2.5 cornice releases. One of these cornices releases triggered a small slab on the slope below. Some natural and explosive-triggered loose dry avalanches were also reported from steep slopes. 

On Wednesday, several natural size 2 wind slabs were reported on north aspects at around 2000 m elevation. Natural loose dry avalanches were also observed on steep slopes. 

Snowpack Summary

20-40 cm of snow typically overlies a variable and potentially weak interface from mid-February which includes a melt-freeze crust on solar aspects, facets, and/or surface hoar. So far this interface has only been a concern in wind-loaded terrain where a slab has formed. In exposed terrain at higher elevations, recent strong northeast winds have caused extensive scouring and wind slab formation. Due to the northerly wind direction, reverse loading occurred meaning there may be wind slabs lingering in unusual places. 

A layer of buried surface hoar from late-January sits 30-60 cm deep in the snowpack and is most likely to be found on north aspects in sheltered areas. Though there haven't been reports of recent avalanches on this layer in this region, it is still on the radar of many operations and could potentially be triggered by large loads such as a cornice fall or a step-down avalanche. 

The lower snowpack is well consolidated, with a crust/facet layer from early-December found 100-150 cm deep. It is currently considered dormant but could become active again later this season. Check out the forecaster blog for more information. 

Terrain and Travel

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.

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.