Avalanche Forecast
Issued: Feb 19th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
cgarritty,
Avalanche Canada
Tricky Moderate. Some wind slabs have stabilized, others sit on triggerable weak layers. Some sheltered snow lacks slab properties, some has just enough to produce a surprising avalanche.
Summary
Confidence
Avalanche Summary
Several natural, rider and explosive-triggered avalanches occurred last week. Notably, a large avalanche triggered by skiers occurred on Saturday. Check this MIN for details.All the recent avalanches were either wind slabs or persistent slabs failing on the weak layers described in the snowpack summary.
The chance of rider-triggered avalanches is expected to persist through this week.
Snowpack Summary
All exposed terrain at treeline and above is highly wind affected by recent strong winds from variable directions.
In sheltered terrain, a new layer of surface hoar is forming on the surface. A sun crust may be found on steep south and west-facing slopes.
An older layer of surface hoar and/or facets may be found buried 20 - 40 cm in sheltered terrain. It is most problematic where wind has added to this depth and contributed to slab formation above the layer.
A crust from late January can be found down 20-50 cm.
Weather Summary
Monday night
Cloudy with isolated flurries. 5 - 10 km/h north alpine wind. Freezing level to valley bottom.
Tuesday
A mix of sun and cloud. 5 - 15 km/h north alpine wind. Treeline temperature -2 °C with freezing level to 1000 m. Possible above freezing layer around 1500 m.
Wednesday
Mainly sunny. 10 - 15 km/h variable alpine wind, easing and shifting west. Treeline temperature -2 °C with freezing level to 900 m. Possible above freezing layer around 1500 m.
Thursday
Mainly sunny. 20 - 30 km/h southwest alpine wind, increasing. Treeline temperature around 0 °C with freezing levels rising to 1400 m.
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.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Persistent Slabs
A mix of buried surface hoar and/or facets sitting on hard crust can be found up to 50 cm deep. This layer is human-triggerable. It has been most problematic on north-facing slopes at upper treeline.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Recent strong winds have come from a variety of directions, transporting snow and forming reactive slabs. Extra caution is recommended at and near ridgetops.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 20th, 2024 4:00PM
