Freezing levels are uncertain, making forecasting for Saturday challenging. If you're traveling on a thickly refrozen surface, chances are avalanche danger's not too bad.
Confidence
Fair - Freezing levels are uncertain on Saturday
Weather Forecast
Saturday: Light snow, starting late in the day. Moderate to strong W winds. Alpine temperature near -6.Sunday: Light to moderate snow. Moderate to strong NW winds. Alpine temperature near -7.Monday: Light snow. Light SW winds. Alpine temperature near -12.
Avalanche Summary
A widespread natural avalanche cycle was observed over the last two days, including loose dry and soft slab avalanches at the beginning of the storm, and wet avalanches as it warmed up. Skiers also triggered wind slabs on lee slopes. Most avalanches were in the size 1-2 range (with a few at size 3) and failed within, or at the base of, the storm snow.
Snowpack Summary
The recent storm dropped anywhere from 40 cm to 1 m of snow at upper elevations, while rain soaked the snowpack below treeline. The freezing level was between 1700 m and 2400 m during the storm. Strong NW through SW winds have redistributed snow into wind slabs and created cornices at alpine elevations. Below the storm snow is a layer of buried surface hoar and/or a crust, which is increasing the reactivity of storm slabs. Deeper in the snowpack, a weak interface buried in mid-February is still on the radar. Although unlikely to be triggered, it remains possible with a very heavy load or from a thin-spot trigger point. A facet/crust layer sits at the base of the snowpack in some areas.As temperatures cool, wet slab/loose wet avalanche problems should improve, but persistent slab concerns at upper elevations will linger, especially on slopes which didn’t avalanche during the storm.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Wet Slabs
Wet Slab avalanches are the release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slabs can be very unpredictable and destructive.