Freezing levels and precipitation amounts are uncertain. Danger may be CONSIDERABLE during periods of heavy rain.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain on Friday
Weather Forecast
FRIDAY: About 5-15 mm of precipitation with strong southwest wind and snow line fluctuating between 1500 and 2000 m.SATURDAY: Mix of sun and cloud with isolated flurries, moderate southwest wind, freezing level up to 1900 m after overnight freeze.SUNDAY: Cloudy with a chance of getting clipped by a storm to the south, freezing level around 1700 m.
Avalanche Summary
Small loose wet avalanches were reported in the southeast part of the region on Thursday. On Wednesday, explosive control produced two small wind slabs in steep alpine terrain in the southeast part of the region. Small avalanches are expected on Friday with the incoming storm.
Snowpack Summary
Moderate rainfall is expected at least up to treeline on Friday. Rain falling on a warm snowpack has the potential to produce loose wet avalanches in any steep terrain. At higher elevations, new snow and wind will form fresh wind slabs and cornices will grow bigger. The snowpack is well settled and transitioning into spring conditions. The bottom third of the snowpack is composed of weak facets, but this deep persistent weakness has not been reactive for a few weeks.
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.
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.