Avalanche Forecast
Issued: Feb 6th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Wind Slabs and Persistent Slabs.
ahanna,
Avalanche Canada
In the north of the region the main concern is wind slabs at upper elevations. In the south, the main concern is deep storm slabs and loose dry sluffing in the new snow. See the problems tab for more details.
Summary
Confidence
Moderate - Recent weather patterns have resulted in a high degree of snowpack variability within the region.
Weather Forecast
Saturday night: Flurries, around 5 cm in the north and snow up to 15 cm in the south, moderate northwest ridgetop wind easing to light, alpine temperature -10, freezing level dropping to valley bottom.
Sunday: Mix of sun and cloud with flurries, up to 10 cm in the south, light northwest ridgetop wind, alpine high -10.
Monday: Sunny, light variable ridgetop wind, alpine high -14.
Tuesday: Mix of sun and cloud, light northerly ridgetop wind, alpine high -17.
Avalanche Summary
Skier triggered wind and storm slabs up to size 1 were reported on Thursday and Friday throughout the region. Last week there were reports of natural, explosive and human triggered avalanches size 1-2, including a widespread natural avalanche cycle Monday night. Many of these failed on the recently buried persistent weak layer.
Snowpack Summary
Snowfall in the south of the region is forecast to conclude today with a nice even blanket of low density snow as temperatures drop and winds die down. In the north, localized areas of soft wind slab may sit over a crust on solar aspects. Recent variable wind directions have resulted in wind loading in atypical terrain features.
30-80 cm of recent snow sits on a persistent weak layer that consists of facets at upper elevations, surface hoar in sheltered areas, a melt-freeze crust below 1600 m, and a sun crust on south-facing slopes.Â
In the south, the underlying snowpack is well consolidated. In the north, a melt-freeze crust from early December may be found 100 to 200 cm deep. Recent reports suggest that this layer is gaining strength and it has been unreactive in recent weeks.
Terrain and Travel
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Be careful as you transition into wind affected terrain.
- Be aware of the potential for large avalanches due to the presence of a persistent slab.
Problems
Storm Slabs
A storm slab problem exists in the south of the region, where recent snowfall has been significant. Cooling temperatures will help to lock up storm slabs but some residual reactivity may still be observed in wind loaded features. Loose dry sluffing may also be observed in the new snow from overnight.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
A wind slab problem exists in the north of the region. Wind slabs may remain reactive especially where they sit over a crust on solar aspects, at ridgetops and roll-overs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A persistent slab problem exists throughout the region. 30-80 cm sits on a buried weak layer that consists of facets, surface hoar, or a crust, depending on location. Avalanche activity has been limited, but we are wary of smaller wind or storm slab avalanches stepping down to this layer.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 7th, 2021 4:00PM
