The avalanche danger may increase if the sun makes an appearance on Tuesday.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
TONIGHT: 5-10cm of snow / Strong southwest winds / Freezing level at 1500m TUESDAY: Mix of sun and cloud / Light to moderate southwest winds / Freezing level at 1500m WEDNESDAY: Light flurries / Light to moderate southwest winds / Freezing level at 1500m THURSDAY: 10-15cm of snow / Moderate southwest winds / Freezing level at valley bottom
Avalanche Summary
Wind slabs to size 1.5 were ski cut on Sunday. They were about 40cm deep and failed on northeast facing terrain at treeline and in the alpine. A size 2.5 cornice collapse was also observed. Increasing southwest winds and light amounts of new snow on Monday night will spark a new round of wind slab activity in higher elevation lee terrain. Periods of sun on Tuesday may also promote loose wet avalanche activity in steep sun-exposed terrain, especially in spots where new snow is exposed to solar radiation for the first time.
Snowpack Summary
On Monday night, generally light amounts of new snow are expected to fall, and strong southwest winds are expected to form new wind slabs in lee features at treeline and in the alpine. The new snow will overlie older wind slabs and settling storm snow from the past few days. About 40-60 cm below the surface, you'll likely find a melt freeze crust. This crust exists in most places except for higher elevation shaded terrain. In many areas there seems to be a reasonable bond between the crust and the overlying snow. I'd still keep an eye on this interface as it has become reactive on some features. Surface hoar buried in early January now lies up to 180cm below the surface and has become less of a concern. Possible triggers for this deep and destructive layer include a large cornice fall or significant warming.
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 Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.