Avalanche Forecast
Issued: Dec 14th, 2021 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeWind slabs continue to be the main concern on Wednesday. Due to recently shifting wind directions, slabs should be expected on all aspects in exposed terrain.
Summary
Confidence
High - Confidence is due to a stable weather pattern with little change expected.
Weather Forecast
An Arctic high pressure system remains the dominant feature for the forecast period bringing cold and dry conditions to the region.
Tuesday Overnight: A few clouds, light to moderate SW winds, treeline temperature around -22 °C.
Wednesday: A mix of sun and cloud, light to moderate SW winds, treeline high around -16 °C.Â
Thursday: Mostly sunny, moderate to strong NW winds, treeline high around -18 °C.
Friday: A mix of sun and cloud, moderate to strong W winds, treeline high around -16 °C.Â
Avalanche Summary
On Monday, a few natural wind slab avalanches up to size 2 were reported on SW-W aspects at around 1700 m near Pine Pass. On Sunday, no new avalanches were reported.
On Wednesday, wind slabs are expected to remain the primary concern in the region. Newer wind slabs which formed on Monday from the NE winds will likely be the most reactive but the older wind slabs from the weekend may still be reactive, especially in steep, unsupported terrain features.Â
Snowpack Summary
On Friday and Saturday, 20-30 cm of new snow was reported along with strong winds from the southwest which formed highly reactive slabs in wind exposed terrain, primarily on north and east aspects. On Monday, the wind switched directions and has likely formed new wind slabs on south and west aspects.Â
The mid and lower snowpack likely contains of a series of early season crusts which may had undergone some faceting. In the deeper snowpack areas of the region, these layers generally appear to have stabilized and gone dormant but they still may be reactive in isolated areas, especially places with a shallow snowpack. Below around 1500 m elevation, the late-November crust can be found down 20-40 cm but generally appears to be unreactive.
Snowpack depth at treeline typically ranges from 50-200 cm, with the shallower value mainly on the eastern side of the range. The alpine snowpack typically ranges from 150-200 cm.Â
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Be alert to conditions that change with elevation and wind exposure.
Problems
Wind Slabs
Wind slabs are expected to be most reactive on south and west aspects as a result of the strong NE winds on Monday. However, north and east aspects also likely still have some reactive wind slabs from the storm on the weekend. As a result, wind slabs should be expected on all aspects in exposed terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 15th, 2021 4:00PM