Regions
Northwest Coastal.
Weather Forecast
Sunday: Freezing Level: 500m, Wind: Mod SW, No significant precip.Monday: Freezing Level: 500m, rising to 750m Wind: Mod S, No significant precip.Tuesday: Freezing Level: 500m, Wind: Light W, No significant precip.
Avalanche Summary
Avalanche activity on Friday was extensive. Below treeline both loose and slab avalanches were reported on all aspects. Natural avalanches to size 3.5 were observed in the treeline and alpine elevations as storm snow failed and ran full path. Sizes were slightly diminished in the south of the region, but still significant as many isolated terrain features failed resulting in both loose and slab avalanches to size 2.
Snowpack Summary
The latest system favored the North where up to 70cm fell as of Friday evening. Southern accumulations dim in comparison coming in around 10cm. As a result, I've weighted northern observations a bit heavier in my analysis. Moderate to Strong winds were initially out of the SW, switching to NW during the later half of the storm creating stiff and deep wind slabs at treeline and in the alpine. Lower elevation slopes received rain and warm temperatures which left many below treeline slopes saturated. The new snow overlies heavy accumulations from earlier in the week that have most likely gained considerable strength. I would imagine that with the ongoing weather pattern, significant cornice development has also taken place.The mid and lower snowpack layers are generally well settled.
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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.