Intense warming is on the way and it's tricky to predict how it will impact the snow. Make conservative terrain choices and avoid sun exposed slopes.
Confidence
Moderate - Freezing levels are uncertain on Wednesday
Weather Forecast
WEDNESDAY: Sunny with valley cloud in the morning, light northwest wind, inversion forming with alpine temperatures reaching -2 C.THURSDAY: Sunny with valley cloud, light wind, inversion with freezing level up to 3000 m.FRIDAY: Sunny with valley cloud, light wind, inversion with freezing level up to 2700 m.
Avalanche Summary
On Tuesday, a large size 3 natural avalanche was reported on a steep north-facing alpine face in the Selkirks. The failure layer is unknown, but it was likely an early season crust. Some sluffing from steep sun-exposed slopes was also reported. Small wind slabs have been reactive to skier traffic on steep convex rolls over the past few days.
Snowpack Summary
The snowpack is about to experience a big change with a week of warm sunny weather ahead. Intense warming is expected on steep south-facing slopes, while dry snow may persist on north-facing slopes. Snow from last week's storms has been redistributed into fresh wind slabs by northwest winds. Roughly 40-80 cm of recent snow sits above crusts from the warm weather in late November. Most reports suggest the snow is bonding to the crusts so far, but there's potential for this layer to become reactive with the intense warming. Snow depths decrease rapidly below treeline, where the primary hazards are rocks, stumps, and open creeks.
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.