Regions
Northwest Inland.
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain on Wednesday
Weather Forecast
Wednesday: Moderate NE wind. Alpine temperature near -10. No precipitation.Thursday: Moderate NW winds. Alpine temperature near -12. Light snow.Friday: Light W wind. Alpine temperature near -9. 8-12 cm snow.
Avalanche Summary
Snowmobilers witnessed naturally-triggered slabs and loose dry sluffs in the Seaton Basin on Monday.
Snowpack Summary
New snow is building up over a weak, faceted old snow surface, which may lead to storm slab development or loose dry sluffing. In wind-affected areas, wind slabs have formed behind terrain breaks such as ridges and ribs. A strong mid-pack overlies a weak base layer of facets and the remnants of a crust. As snow builds up incrementally over these weaknesses, avalanche danger is also likely to gradually increase. Under these circumstances, it can be hard to evaluate if/when the tipping point will occur which leads to slab avalanches failing on persistent weak layers. Keep track of snow loading in your local area and adopt a cautious approach to terrain selection.
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.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.