Danger is declining as the weather clears and cools, but there is uncertainty about how quickly layers in the upper snowpack will strengthen. Evaluate snow and terrain carefully.
20 to 40 cm of recent storm snow will bond relatively quickly in most areas, but may still produce avalanches in specific terrain features. This includes wind loaded slopes and open convexities at treeline where it may sit above sun crusts or feathery surface hoar.
WEDNESDAY NIGHT: Mostly cloudy skies with some convective flurries bringing trace amounts of snow, light wind from the southwest, treeline temperatures drop to -8 C.
THURSDAY: Mostly cloudy skies with isolated flurries bringing trace amounts of snow, light wind from the northwest, treeline temperatures reach -5 C with freezing level climbing to 1200 m.
FRIDAY: Mostly sunny, light wind from the northeast, treeline temperatures around -8 C.
SATURDAY: Mix of sun and cloud, light wind from the north, treeline temperatures around -10 C.
Widespread storm slab avalanche activity was observed on Monday and Tuesday. The storm slabs were very reactive to skiers, producing size 1-1.5 avalanches on convex rolls. These avalanches ran on recently buried crust and surface hoar layers, roughly 20 to 40 cm deep. Larger (size 2-2.5) natural avalanches were observed on bigger alpine slopes, and wet loose avalanches occurred at lower elevations. The reactivity of the storm slabs is likely diminishing rapidly, although the potential to trigger them exists on some slopes.
There was concern about the warm storm producing a spike in large persistent slab avalanches, but there was only one isolated report of a size 3 avalanche in the Esplanade Range on Tuesday (in the Selkirks). This was a size 3 avalanche that failed on a crust layer on a south-facing slope. Based on the current weather trends and lack of recent avalanches, avalanches on persistent weak layers are now unlikely.
Recent storm snow has likely settled into 20 to 40 cm of heavy powder at upper elevations and wet/crusty snow below treeline (below 1800 m near Revelstoke and below 1500 m near Blue River). Reactive slabs may be found on wind loaded slopes and perhaps some isolated areas where this snow sits above sun crusts or feathery surface hoar. The snowpack is generally well settled below the new snow, with previous persistent weak layers showing improving trends over the past weeks. This includes two layers of surface hoar and/or crusts buried 50 to 100 cm deep, which are considered unreactive under the current conditions.
