Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
Southwesterly winds built wind slabs on leeward northerly and easterly slopes. If triggered, wind slab avalanches may step down to deeper layers resulting in larger avalanches.
Recent avalanche activity indicates an unstable snowpack & remote-triggering remains a serious concern.
Retreat to more conservative terrain if you encounter signs of instability.
Southwesterly winds built wind slabs on leeward northerly and easterly slopes. If triggered, wind slab avalanches may step down to deeper layers resulting in larger avalanches.
Weak layers formed in January persist within the upper 100 cm of snow. The more the snowpack warms up and weakens over these layers, the more conservative your terrain selection should be.
Wet loose avalanches will become more likely as daytime warming and sun melt the upper snowpack. There is also concern that they may step down to persistent weak layers.
Wed: Explosives control triggered avalanches up to size 3.5 & skiers remotely triggered a size 2.
Tues: Numerous large (size 2-2.5) avalanches with natural, explosive, & human triggers occurred.
Mon: Many natural & human triggered avalanches were reported (size 1-2.5)
Sun: A widespread, natural avalanche cycle was reported (up to size 3).
Looking forward: Evidence indicates storm slabs and persistent weak layers remain primed for human triggering.
A recent storm deposited 20 to 50 cm of snow across the region and southwesterly winds formed reactive slabs on leeward slopes. At lower elevations and on sun-exposed slopes, warm temperatures and solar radiation resulted in a crust or moist snow. In wind-sheltered areas, the storm snow generally rests on a weak layer of facets or surface hoar, while elsewhere it overlies a widespread crust. Additional weak layers formed in January are found at varying depths within the upper 100 cm of snow. These include weak faceted snow, sun crusts on south-facing slopes, and surface hoar in shaded terrain. Otherwise the mid and lower snowpack is generally well-settled and strong.
Thursday Night
Partly cloudy. 20 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level falling to valley bottom.
Friday
A mix of sun and cloud. 15 to 20 km/h southwest ridgetop wind. Treeline temperature +1 °C. Freezing level rising to 2000 m.
Saturday
A mix of sun and cloud. 25 to 45 km/h south ridgetop wind. Treeline temperature +2 °C. Freezing level rising to 2200 m.
Sunday
Cloudy with 1 to 5 cm of snow. 20 km/h variable ridgetop wind. Treeline temperature -1 °C. Freezing level rising to 1600 m.
More details can be found in the Mountain Weather Forecast.