Natural avalanches unlikely, human triggered possible.
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.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Northwest Inland.
Confidence
Fair - Intensity of incoming weather is uncertain
Weather Forecast
Tuesday: trace amounts of snow - light to moderate southwest winds - freezing level at surface Wednesday: Very light snowfall - light to moderate south winds - freezing level at 600m Thursday: light to moderate snowfall - moderate to strong south winds - freezing level at 1100m
Avalanche Summary
No new avalanches to report. We'd love to hear about what you've seen in the field. Any observations can be sent to: [email protected].
Snowpack Summary
Melt freeze crusts exists on most aspects below 1000m and on many sun-exposed slopes as high as 1600m. More recently, intense wind-loading and light snowfall accumulations have taken place with snow surfaces either getting scoured or packed into hard wind slabs. The mid February interface, down around 60cm, is variable and generally consists of a strong melt freeze crust below 1000m. Above that elevation, expect to find buried facets, and/or surface hoar (in more sheltered areas), and/or a sun crust on southern aspects. The surface hoar is not widespread, but has been responsible for larger avalanches that occurred last week. This layer should be on your radar, as it may be susceptible to rider triggers.
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.