Avoid exposing yourself to slopes that are getting affected by the springtime sun.
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Sunday
Weather Forecast
Light snow fall is expected on Sunday with sunny breaks. Flurries are possible on Monday. On Tuesday, a ridge moves in, starting a few days of fine, sunny weather. The freezing level is around 1500 m by day, falling towards valley floor by night. Winds are generally light.
Avalanche Summary
Several cornice falls have been reported in the last few days, some of which have triggered slabs on slopes below.On Wednesday, a size 2 persistent slab was triggered in a permanently closed area at a ski area. It may have started in the March persistent weak layer before it stepped down to fail at ground. While the likelihood of triggering a large persistent slab avalanche has gone down, the consequences remain high.
Snowpack Summary
Recent 10-25 cm snow was shifted by variable strong winds into wind slabs on lee slopes above about 2000 m. Cornices are large and touchy in some spots. The new snow sits over a crust which is generally becoming more supportive. Low elevations sport an isothermal snowpack, which is now capped by a refrozen crust.Persistent weak layers in the upper snowpack remain a lingering concern, although they seem to be slowly gaining strength. In the north of the region, the mid-March crust/facet layer is down 40-60cm. The mid-February crust/facet/surface hoar layer, down about 80 cm, may also still be reactive in isolated areas. Weak layers which formed earlier in the winter are also a concern in certain spots.
Problems
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.
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.