Little overnight freeze below 1900m translates to moist surface layers that are susceptible to natural and human triggering. Watch for an increasing avalanche danger with daytime warming.
Weather Forecast
Cloudy with sunny periods, light SW winds and a freezing level around 1900m today. Solar input will rapidly destabilize surface snow. Tuesday freezing levels should rise with an alpine high of +1C, flurries and moderate to strong gusty SW winds. Wednesday the trend is to slightly cooler temps, scattered flurries and light ridge winds.
Snowpack Summary
Rapid warming and solar input yesterday destabilized surface storm snow resulting in a wide spread avalanche cycle. Temperatures stayed above freezing as high as 1900m overnight. Moist surface layers will be prone to sloughing as temps warm today. On solar slopes the storm snow sits on a persistent crust.
Avalanche Summary
Over 40 avalanches recorded in the highway corridor yesterday up to size 3. Widespread avalanche cycle in the backcountry involving surface layers of snow. With no overnight recovery surface layer sloughing is expected to continue.
Confidence
Intensity of incoming weather systems is uncertain
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.
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.