Avalanche Forecast
Regions: Cascades - North West.
You can trigger Wind Slabs above treeline. Avoid stiff supportive pillows of snow and cross-loaded features on slopes 35 degrees and steeper. Strong and gusty winds may have formed Wind Slabs lower on slopes than where they typically form or in unique locations.
Detailed Forecast
You can trigger recently formed Wind Slabs at upper elevations. Stay safe by avoiding obviously wind loaded features. Cracking in the snow, stiff, supportive surfaces, and wind sculpted features are all indicators that you should avoid a piece of terrain. Very strong and gusty winds may have formed slabs where you would not normally see them. Use caution in areas that could be cross-loaded mid-slope. If you venture above treeline, know that observations have been minimal at that elevation for 2-3 weeks. Use caution and take time to assess the upper snowpack and any recently drifted snow.
Near and below treeline, avalanches are unlikely, though not impossible. Continue to use normal caution. Always carry a beacon, shovel, and probe and use travel practices that minimize your exposure to avalanche terrain. Stay out from under slopes where other parties may be traveling on wind exposed higher elevation slopes.
There are some remaining considerations to stay safe in the mountains. While Glide avalanches are unlikely, they can be dangerously large and difficult to predict. It’s worth giving these avalanches a little more time before we forget about them. Avoid stopping under slopes with steep rock slabs that are still holding snow. Avoid traveling near glide cracks as they can be dangerous if you fall in them. Many lower elevation slopes may be firm and icy. A slip and fall in steep terrain above rocks or cliffs could be dangerous.
Snowpack Discussion
No avalanches have been reported in the past 48 hours. Recently observed avalanche activity includes small triggered Wind Slabs on Wednesday and large Glide avalanches running on February 3rd and 4th. While we're still keeping an eye on some deeply buried crusts, there are no known Persistent Weak Layers in this zone.
Cold and clear conditions are moving into the region for the first time in weeks. Freezing levels dropped to low elevation slopes Thursday night and mostly stayed well below Heather Meadows. Light rain fell to upper elevations on Wednesday and Thursday with freezing levels reaching up to 5,000ft. Strong and gusty winds formed Wind Slabs above treeline on Tuesday through Thursday.
Observations
North
On Wednesday, NWAC Pro Observer Lee Lazzara was touring around Table Mountain. He found 2-6" of recent snow now moist on the surface above a mostly strong snowpack with no lingering instabilities. He saw lots of glide cracks which could be dangerous, particularly if covered by fresh snowfall in the future.
On Wednesday Mt. Baker Patrol reported one small triggered Wind Slab avalanche while ski-cutting inbounds terrain.
Avalanche Problems
Wind Slabs
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.
Wind Slabs form in specific areas, and are confined to lee and cross-loaded terrain features. They can be avoided by sticking to sheltered or wind-scoured areas..
Wind Slab avalanche. Winds blew from left to right. The area above the ridge has been scoured, and the snow drifted into a wind slab on the slope below.
Wind slabs can take up to a week to stabilize. They are confined to lee and cross-loaded terrain features and can be avoided by sticking to sheltered or wind scoured areas.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 1