Human triggering of avalanches remains likely and conservative terrain selection is critical. If the sun breaks through the clouds natural avalanches are possible. Minimize exposure to overhead avalanche terrain and slopes threatened by cornices.
Weather Forecast
Generally mild conditions will continue. The forecast is for mostly cloudy skies with light flurries. Sunny breaks are possible especially at higher elevations. The sun may destabilize the new snow, and avalanches are possible during sunny periods. Freezing levels are ~1300m and moderate W'ly winds are expected at ridgetop.
Snowpack Summary
Up to 20cm of dry snow has buried moist snow from the weekends rain. 140cm have fallen since Feb 1 and settled to ~1m of settled storm snow over the Jan 30 layer. This layer formed a crust to 2200m with spotty surface hoar distribution. Jan 15 surface hoar layer is down 100-150cm and continues to be reactive in tests.
Avalanche Summary
Rain switched to snow yesterday and avalanche activity tapered off. Since Thursday, a large avalanche cycle occurred with avalanches to size 3.5 running from all elevations into valley bottoms. Reports from skiers in the region are of touchy conditions, with remote triggering of slabs up to 1m deep and wide propagations.
Confidence
Timing or intensity of solar radiation is uncertain
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.