Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Northwest Inland.
The timing of the this weekend's big warm-up is difficult to forecast. If Sunday ends up being the warmer day, Sunday's avalanche danger may be higher than posted, especially in deep snowpack areas.
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Sunday
Weather Forecast
Sunday: Clear skies / Light and variable winds / Freezing level at about 2000mMonday: Clear with increased cloud late in the day / Light to moderate southwest winds / Freezing level at about 1500mTuesday: Overcast skies with very light precipitation / Light westerly winds / Freezing level at about 1300m
Avalanche Summary
At the time of publishing no new avalanches were reported, although I suspect natural loose wet and slab activity may have occurred with Saturday's warm temperatures. Below is a link showing natural avalanche activity over the past few days (sometimes photos speak louder than words):Hankin-Evelyn Trail-crew update
Snowpack Summary
Up to 30 cm of recent storm snow fell at upper elevations. At lower elevations rain saturated the snowpack and melt-freeze conditions exist up to 1200 m on all aspects. At higher elevations the new snow overlies a rain crust which exists to about 2000m. Strong SW winds have built thick wind slabs on leeward aspects and a poor bond may exist, especially where the buried crust exists. Two persistent weak interfaces exist deeper in the snowpack. The early March layer can be found down 75 - 100cm. The early February crust/facet/surface hoar combo is down 150 - 200cm. Particularly in deeper snowpack areas, these layers may have become overloaded by the recent storm. They should remain on your radar, and could become reactive with solar radiation and high freezing levels.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.
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.