We have a reactive layer down 50cm and overnight winds that have consolidated the slab further. Stick to forested and low angle terrain if you head in the backcountry. Limit your exposure to overhead hazard.
Weather Forecast
Snow should be tapering off today as a brief ridge of high pressure builds. Expect cloud and light snow with temperatures remaining steady at around -5 and winds in the 20-40km/h range at 2000m from the west. Pacific frontal system is forecast to hit the interior Tuesday afternoon bringing moderate amounts of snow and heavier into Wednesday.
Snowpack Summary
50cm of recent storm snow sits over the Dec 17 surface hoar, 10-20mm, which sits on or just above a rain crust to 2100m and on settled snow above 2100m. The Dec 9, surface hoar size 3-5mm is visible in certain areas down ~80cm. Mid-pack is well settled with the Nov 9 crust/facet layer in the bottom 30cm.
Avalanche Summary
Field team on Mt Fidelity, 1900m to 2100m, reporting touchy conditions with several skier remote and control triggered size 1.0 and 2 size 2.0 avalanches with wide propagation down 30cm running on the Dec 17 surface hoar/crust layer. Numerous size 2.0 natural slab avalanches observed yesterday east of the Rogers Pass summit in the highway corridor
Confidence
Due to the number and quality of field observations
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.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.