Avalanche Forecast
Issued: Feb 8th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs, Cornices and Wind Slabs.
TRettie,
Avalanche Canada
Keep an eye on the snow surface, as it gets moist the likelihood of triggering avalanches will increase. Avoid overhead hazards.
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations.
Weather Forecast
Tuesday night: no new snow expected. Moderate to strong northwest winds with a low of -2 at 1900m.
Wednesday: Mainly sunny with moderate northwest winds. Freezing levels climbing to around 2300 m.
Thursday: Mainly sunny with moderate west winds. Freezing levels reaching near 2500 m with an inversion.
Friday: Sunny with freezing levels around 2000m. Light northwest winds.
Avalanche Summary
No new avalanches were reported on Sunday or Monday but observations were limited.Â
This MIN report from Saturday describes a natural size 1.5 slab avalanche on a south aspect as well as shooting cracks and whumpfing while travelling. It also suggests the surface snow was getting warm and consolidating into a slab.Â
Snowpack Summary
A new melt-freeze crust is expected on solar aspects into the alpine and on all aspects at lower elevations. This crust will likely break down and become moist as the freezing level rises and the sun comes out. Ongoing periods of strong to extreme wind from the southwest through northwest have formed reactive wind slabs and large cornices in exposed terrain at higher elevations.Â
The January 30 interface is now typically down 20-40 cm and consists of a melt-freeze crust at lower elevations and on solar aspects extending into the alpine, spotty surface hoar in sheltered areas at and below treeline, and small facets in some areas. The January 18 rain crust is probably now around 40-70 cm deep and may have weak faceted snow above.Â
The early December crust/facet persistent weak layer is now 100-200 cm deep. This layer produced numerous very large avalanches in January but is now considered dormant. See this forecaster blog on how to manage this layer as it may come into play again later this season.Â
Terrain and Travel
- Be aware of the potential for large avalanches due to the presence of buried weak layers.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Cornices become weak with daytime heating or solar exposure.
- Be careful as you transition into wind affected terrain.
Problems
Persistent Slabs
The late-January crust/surface hoar/facets down 20-40 cm remains a concern mainly where surface hoar may be preserved.
In the neighbouring Lizard-Flathead region, the mid-January crust/facet layer down 40-70 cm woke up over the weekend and may also be a concern for the South Rockies.
Likelihood of triggering this layer could increase as the freezing level rises.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Cornices
Large cornices are expected with ongoing strong to extreme wind over the past week. A cornice failure has the potential to trigger a slab avalanche on the slope below.
Aspects: North, North East, East, South East, South, South West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Wind Slabs
Recent strong winds from the SW through NW have formed reactive wind slabs in exposed terrain at higher elevations.
Aspects: North, North East, East, South East, South, South West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 9th, 2022 4:00PM
