Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
Expect increased cloud on Thursday with trace amounts of snowfall. Very light snowfall should occur sporadically throughout friday and Saturday morning with possible clearing by Saturday afternoon. Winds are expected to be light and northwesterly trending to light and variable by Saturday. Daytime freezing levels are forecast to remain at about 1200m (dropping to surface overnight) throughout the forecast period.
Avalanche Summary
A few newly developed windslabs to size 2 were observed in the alpine on Monday and Tuesday.
Snowpack Summary
Very warm alpine temperatures from last weekend melted snow surfaces. With more recent cooling a crust now exists to ridge top on solar aspects. In general, the upper snowpack is now well settled and riders have gained increased confidence on steeper terrain. The one exception may be new wind slabs that formed at higher elevations with moderate alpine winds on Monday/Tuesday. Deeper weaknesses in the snowpack seem to less of a concern; however, in the southern end of the region there is still talk of basal facets as some operators are avoiding thin and rocky alpine features. This represents a low probability-high consequence scenario. Large, unstable cornices are also widespread in the alpine. If you're heading into the mountains, it's a good time to take stock of evolving layers (crusts, surface hoar) that may be an issue when it finally snows again.
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.