Regions
Northwest Coastal.
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Monday: Some clouds developing. Freezing level around 1500 m. Light southerly winds. Tuesday: Light precipitation. Freezing level around 1500 m.Wednesday: Light to moderate precipitation. Freezing level rising to around 1800 m.
Avalanche Summary
Recent reports include wet loose avalanches up to size 2.5 in response to direct sun exposure. Cornices have also been failing over the past few days, some of which triggered wind slab avalanches up to size 2 on the slope below. Large glide avalanche activity also continued. On Saturday, a size 3 glide release removed trees and left a 4-5 m deposit near Shames. Glide slabs can be unpredictable. Any slopes sporting glide cracks are best avoided.
Snowpack Summary
The snow surface consists of a sun crust on solar aspects and at low elevations (becoming moist during the day), surface hoar on shady slopes up into the alpine, and dry settling or faceting snow on high north aspects. Pockets of wind slab are likely in exposed leeward alpine terrain. Sheltered shady slopes may be harboring buried surface hoar and/or preserved old storm snow from last week, which isn't as stable. Daytime warming or sun-exposure may cause surface snow to lose cohesion and cornices to weaken. Glide cracks have opened up, especially on steep rocky terrain features.
Problems
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
Wet Slabs
Wet Slab avalanches are the release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slabs can be very unpredictable and destructive.