Watch for wind slabs in unusual places as we head into a clear cold week
Confidence
High - The weather pattern is stable
Weather Forecast
MONDAY: Sunny, light east winds, alpine temperatures around -20.TUESDAY: Sunny with cloudy periods, light northeast winds, alpine temperatures around -15.WEDNESDAY: Sunny with cloudy periods, light northeast winds, alpine temperatures around -15.
Avalanche Summary
Avalanche observations on Saturday included isolated size 1 loose dry avalanches in steep terrain and one natural release of a size 2 avalanches on a northeast treeline slope. After a windy day on Sunday, expect an increase in wind slab avalanche activity on lee and cross-loaded features.
Snowpack Summary
The region received 50 to 90 cm of new snow between Christmas and New Years. This snow has been redistributed by strong winds that have come from a variety of directions and loaded leeward and cross-loaded features. Sunny skies will promote settlement of the snow on open south-facing slopes. The mid-December facet/surface hoar interface can be found buried 70-120 cm deep, and has been showing signs of gaining strength recently with little to no recent avalanche activity in the region. The lower snowpack is well bonded and features a thick rain crust near the ground.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.