Avalanche Forecast
Issued: Feb 20th, 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.
mconlan,
Avalanche Canada
Conservative terrain travel is warranted with touchy wind slabs and cold weather.
Summary
Confidence
Moderate
Avalanche Summary
Some small to large (size 1 to 3) wind and storm slab avalanches were observed on Sunday and Monday from recent storm snow. Check out the MIN for one notable avalanche observed on Saturday.
Looking forward, we anticipate that the storm snow will continue the bonding process to the snowpack. Wind slabs may continue to be reactive to human traffic. Cold weather should reduce the likelihood of avalanches in the coming days, though triggering deeper weak layers is always possible, where they exist.
Snowpack Summary
The region has received anywhere from 40 to 80 cm of recent storm snow, which was redistributed into wind slabs and large cornices. The wind was predominantly southwest but is switching to northeast, meaning that wind slabs may be found on all aspects.
The mid-pack is gaining strength and consists of rounding facets and decomposing melt-freeze crusts.
A weak layer of large and weak facets is found near the base of the snowpack. This layer is most likely to be triggered in thin, rocky alpine and upper treeline terrain.
Weather Summary
Monday Night
Cloudy with snowfall, accumulation 5 to 15 cm, 40 to 60 km/h northeast wind, treeline temperature -20 °C.
Tuesday
Mostly sunny skies with no precipitation, 40 km/h northeast wind, treeline temperature -25 °C.
WednesdayMostly sunny skies with no precipitation, 40 km/h northeast wind, treeline temperature -28 °C.
ThursdayMix of sun and cloud with no precipitation, 40 km/h northeast wind, treeline temperature -30 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Wind slabs are most reactive during their formation.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
Problems
Wind Slabs
Strong northeast wind is forecast, which will redistribute recent storm snow into wind slabs in exposed terrain. Slabs may be found on all aspects due to a shifting wind direction from southwest to northeast. Assess for slabs in steep terrain prior to committing.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of large, weak facets sits near the base of the snowpack. This layer is most prominent in the upper treeline and lower alpine elevations. You are most likely to trigger this layer on thin, shallow, rocky slopes. Cornice falls or other avalanches could also trigger this layer, forming large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 21st, 2023 4:00PM
