Northwest Inland

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Good

Snow starting Thursday afternoon is expected to bring 2-5 cm by Friday morning, another 5-10 cm Friday afternoon into Saturday, before generally dry conditions prevail for Sunday. Generally light but gusty souheasterly alpine winds are expected throughout the forecast period. Daytime high freezing levels should hover around 1400 m each day.

Reports from Wednesday are limited to just one new Size 2 natural wind slab avalanche on a northeast facing alpine slope below a ridge crest. However, reports from Tuesday include several small natural and skier triggered wind slab avalanches in lee and cross-loaded treeline and alpine terrain. The reports mentioned surprisingly little large avalanche activity given the strong winds and amount of fresh snow available for wind-transport.

Approximately 15-30 cm of dense storm snow overlies a variety of crusty old surfaces. Recent strong winds have scoured windward slopes and loaded leeward slopes below ridgecrests and behind terrain features. Persistent weaknesses buried in the upper snowpack may include hard crusts and/or facet crystals, although not much is known about the reactivity or spatial distribution of these layers. At the base of the snowpack, weak facets may be found. Cornices are large and potentially fragile. Unpredictable, full-depth glide avalanches are also a concern on low elevation slopes with smooth ground cover (grassy slopes, rock slabs, etc.) where large cracks have formed from the snowpack slipping on the ground.