Wind slabs may be reactive to human triggering at upper elevations.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
MONDAY NIGHT - Cloudy with isolated flurries / southeast winds, 10-25 km/h / alpine low temperature near -4 C / freezing level 1300 mTUESDAY - A mix of sun and cloud with scattered flurries, up to 10 cm / northwest winds, 20-40 km/h / alpine high temperature near -3 C / freezing level 2000 mWEDNESDAY - Cloudy with sunny periods and scattered flurries, 5-15 cm / west winds, 15-35 km/h / alpine high temperature near -3 C / freezing level 1800 m THURSDAY - Cloudy with sunny periods and isolated flurries, up to 10 cm / alpine high temperature near -4 C / alpine high temperature near -5 C / freezing level 1800 m
Avalanche Summary
Small (size 1-1.5) wind slabs were reactive to skiers on Sunday, generally around ridgetops and steep, convex terrain above 2200 m. The most reactive deposits were in immediate lee features, including a size 2 wind slab avalanche remotely triggered from a rocky saddle 10 m away. On Saturday, there were a few reports of natural and human triggered wind slab avalanches, mainly in the alpine on north and east facing slopes.On Thursday, there were a few reports of natural and human triggered storm and wind slab avalanches in the alpine, as well as a few human triggered loose wet avalanches.
Snowpack Summary
10-20 cm of recent storm snow sits on a melt-freeze crust on all aspects except for north slopes above 2000 m, where it sits on dry snow. Recent snowfall amounts taper quickly below treeline.The base of the snowpack is composed of sugary faceted snow. The likelihood of triggering an avalanche on this layer is lower during colder periods and elevated during intense warming.Snow is disappearing rapidly at lower elevation.
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.