Fresh storm slabs are sitting on a new crust at treeline and below. Use small slopes with low consequence to test the bond of the storm snow.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Seasonal temperatures and isolated flurries through the weekend. Significant warming Monday onwards. SATURDAY: Mostly cloudy with isolated flurries / Light, southwesterly winds/ Freezing level around 900 m. SUNDAY: Mix of sun and cloud / Light, southwesterly winds / Freezing level rising to 1000 m. MONDAY: Sunny with cloudy periods, warming significantly with highs to +5 Celsius / Moderate southwesterly winds / Freezing level around 2200 m.
Avalanche Summary
No new avalanches reported.
Snowpack Summary
We've had 15-20cm of wet heavy snow at treeline since Thursday afternoon, sitting on 20-30 cm drier snow. This makes 50-70 cm of cumulative storm snow which is bonding well to a knife hard crust buried Feb 3rd. In the alpine, where all of the precipitation has fallen as snow, the storm slabs will remain touchy and likely to human trigger on Saturday. The mid and lower snowpack are settled and well bonded with the average snowpack depth at treeline 250-300 cm.
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.