Temperatures are expected to remain below zero in the Alpine (around -3.0), but may get a bit warmer when combined with solar warming. If the sun is out and it feels warm, watch for loose moist snow falling out of cliffs and steep terrain.
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Wednesday
Weather Forecast
Overnight and Wednesday: An upper ridge of High pressure continues to dominate the interior regions. Large valleys should expect cloud with mostly clear skies above. Alpine temperatures are forecast to be warmer than the valleys, but should still be about -3.0. Light winds and no precipitation for the forecast period.Thursday: The temperature inversion is forecast to persist on Thursday causing warmer temperatures in the alpine than at valley bottoms. Friday: Becoming cloudy during the day with moderate westerly winds as a weak upper disturbance slides into the region.
Avalanche Summary
Recent avalanche activity in the region has been limited to loose snow avalanches running in steep terrain and isolated slab releases to size 2 from steep rocky terrain in the alpine. Glide cracks continue to open.
Snowpack Summary
New surface hoar continues to grow in areas that are sheltered from the wind. Recent surface hoar is buried beneath a thin layer of cold dry snow. Thin wind slabs continue to develop due to the availability of loose snow for transport. Continued winds are expected to stiffen these soft wind slabs. Deeper weak layers have not been reactive.
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.
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.