Avalanche Forecast

Issued: Feb 27th, 2022 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs.

Avalanche Canada jleblanc, Avalanche Canada

 Watch for blowing snow and see where it is being transported. Fresh and reactive wind slabs are likely forming in leeward side of ridgetops. 

Summary

Confidence

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

Weather Forecast

A series of storms are set to be impacting the region in the next few days. Light to moderate snowfalls, rising freezing levels, and warmers temperatures are expected until mid-week. 

Sunday night: Flurries up to 5 cm. Freezing level returning to valley bottom. Alpine temperatures around -8 C. Moderate southerly winds gusting 50 km/h.

Monday: Flurries. Freezing level rising to 1200 m. Alpine temperatures around -2 C. Moderate southerly winds.

Tuesday: Snow 10-20 cm. Freezing level rising to 1200 m. Alpine temperatures around -2 C. Moderate southwesterly winds gusting to 50 km/h.

Wednesday: Flurries up to 5 cm. Freezing level rising to 1200 m. Alpine temperatures around -2 C. Moderate southerly winds.

Avalanche Summary

No new natural avalanches were reported in the last 24 hours. 

Snowmobilers were able to trigger a few small wind slabs (size 1) on convex alpine lee features around Hasler. Check out our field team's MIN report for photos and details. 

Snowpack Summary

10-15 cm of fresh snow has fallen Sunday throughout the region. This new snow is now covering a wide variety of surfaces, including heavily wind-affected surfaces on most alpine slopes, fresh wind slabs on any open features, thin sun crust on steep south-facing slopes at all elevations. Under it, a thick melt-freeze crust is present on all aspects and elevations, which is at the surface in exposed areas.

Below the crust, 10-40 cm of more settled snow exists above the late January weak layer. This layer consists of weak faceted snow, a melt-freeze crust, and surface hoar crystals in isolated sheltered areas at treeline and below. In most areas, this layer is bridged by the thick crust above it. The base of the snowpack is expected to be weak and faceted in shallow, rocky slopes east of the divide.

Terrain and Travel

  • Wind slabs are most reactive during their formation.
  • Be carefull around freshly wind loaded features.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • Closely monitor how the new snow is bonding to the crust.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong winds likely redistribute fresh snow (10-15 cm) and build reactive wind slabs on any exposed terrain, lee features, and around ridgelines. Use increased caution around treeline or alpine features where these slabs may overlay a weak layer, sun crust or hard wind slabs. Uncertainty remains in how well the developing slabs will bond to hard and smooth surfaces.

Aspects: North, North East, East, North West.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Feb 28th, 2022 4:00PM