Minimal snow fall hasn't changed the wind slab problem, but light winds and flurries have added a loose dry concern for ice climbers in high alpine terrain.
Weather Forecast
Isolated flurries tonight with moderate ridge winds. Tomorrow will continue with the flurries, but the winds will drop off to the light range. The alpine temps will hover around -10 degrees.
Avalanche Summary
1 loose dry avalanche (sz1.5) was witnessed this afternoon. It started out of very steep alpine terrain near the Old Goat glacier. Climbers should take note of this as it was in climbing terrain.
Snowpack Summary
Flurries overnight and today have left a dusting of new snow at all elevations. Unfortunately this is not enough to change the snowpack in a positive way. Below treeline is still considered to be below thresh hold for avalanches. Treeline is where the avalanche potential starts. Despite the dusting of new snow, we are still seeing the evidence of the wind event from last week. Many exposed alpine ridges are blown free of snow, which leads us to believe that there are wind slabs in lee areas. Below the windslabs, the crusts from earlier this month are still very prominent. The "Trump" crust (buried Nov 12th) is by far the most prominent and is down 30-50cm's. So far the bond within the upper pack appears to be strong with only "hard" failures noted, suggesting that the snowpack is relatively strong.
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.
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.