Pay close attention to how the new snow is bonding to the old snow surfaces, especially where it sits on surface hoar and buried crusts.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain on Thursday
Weather Forecast
Wednesday: Mix of sun and cloud. Alpine temperatures near -2 and freezing levels near 1900m. Ridgetop winds light from the South.Thursday: Snow amounts 5-10 cm, accompanied by strong ridgetop winds from the southeast. Freezing levels near 1700 m.Friday: Cloudy with isolated flurries. Alpine high of -11 and freezing levels near 1500 m. Light to strong gusty southwest winds.
Avalanche Summary
On Tuesday, one size 1 wind slab was reported, entraining moist snow during warming. A few natural loose dry avalanches up to size 1.5 occurred on Monday.
Snowpack Summary
Up to 25 cm of low density snow fell Sunday overnight into Monday, combined with last weeks snow, this brings the total amount 30-40 cm. This new snow sits on a wide variety of old surfaces: a melt-freeze crust on sunny aspects, isolated old wind slab in the alpine near ridge crests and predominantly dry snow or surface hoar (up to 20mm in size) on north aspects above 1500-1800m.A weak layer of surface hoar buried mid-February exists in parts of the region around 50 to 80 cm deep. The lower snowpack is weak with a combination of crusts and facets near the bottom of the snowpack that are widespread.
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.
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.