New snow forecast for the overnight period will add additional load onto last weekends storm snow. Winds are expected to be light but stronger values will quickly form new soft slabs and compound the cornice concerns that exist now.
Weather Forecast
Forecasts are calling for 10-15cm of new snow overnight with models differing in when the snowfall periods will end - either Thursday Am or late in the day on Thursday. Winds are forecast to remain light from the W-SW. Temperatures are on a slow steady rise.
Avalanche Summary
No new observations observed or reported today.
Snowpack Summary
The recent storm snow has settled out into a soft slab approx 30cm thick in areas near treeline. Compression test results at 2400m on a 30 degree northeast aspect in the Tent Ridge area today showed moderate results at the interface between the storm snow and an old windslab. Additional testing produced hard results on a deeper windslab down 60cm. The shears were Sudden Planar in character.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.