Avalanche Forecast
Issued: Jan 12th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
SH,
Avalanche Canada
Warm and windy on Friday. Although only a few cm of snow is expected Friday, this is a significant change in the weather. There is uncertainty as to if and how this will impact the deeper weak layers, but confidence is low.
Summary
Confidence
Moderate
Avalanche Summary
Lake Louise ski hill had 1 explosive result to size 2 that stepped to ground in some spots. No other avalanches were observed or reported.
Snowpack Summary
10-20 cm of loose snow sits over a denser mid-pack which has formed a slab over the weak facet layers below - this loose snow is getting blown into slabs. The December 17 weak layer is down 25-60 cm and becoming less reactive. The November 16 deep persistent layer of facets and depth hoar is near the base of the snowpack, continuing to show sudden failures. Puzzle Peak snow profile from Tuesday.
Weather Summary
Warm and windy will be the story for Friday. Only a few cm of snow with freezing levels up to 2000m (highest in eastern portions near Banff). Winds will stay elevated with alpine speeds of 60-80 km/h in the AM and 50-60km/h in the afternoon.
Terrain and Travel Advice
- Use careful route-finding and stick to moderate slope angles with low consequences.
Problems
Wind Slabs
With up to 20 cm of loose snow available for wind transport, Friday's increasing winds may create fresh, sensitive wind slabs in leeward areas.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
The lower snowpack is comprised of weak facets, with a slab formed over this weakness at treeline and in the alpine. This weak basal layer is uniform across most of the region and has the potential for human triggering and larger avalanches. With the forecasted warmth, we may see some activity on deeper facets below the treeline, especially in the East where temperatures will be the warmest.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 13th, 2023 4:00PM
