Weather Forecast
A weak ridge of high pressure will allow a few sunny breaks, with showers and freezing levels around 1900m. Strong S-SW winds will continue. Overnight a cold front will bring up to 13mm of precip with freezing levels lowering to 1000m. Light precip and broken clouds are expected through Tuesday as another ridge starts to build off the coast.
Snowpack Summary
13mm of rain at Rogers Pass, with freezing levels hovering around 1900m over the last 24hrs. Surface wet grains overly a near isothermal snowpack with various crusts/PWL in top meter. ~20cm of storm snow above 1900m will have been transported by strong S'ly winds, loading lee slopes and forming pockets of windslab which may bond poorly.
Avalanche Summary
Warm temps and rain triggered several natural avalanches yesterday. Over the last 2 days size 2-2.5 loose, wet avalanches have been occurring on all aspects, from start zones of 2000-2700m. Cornice failures remain a concern for triggering slab avalanches, mostly failing on PWL's in the top meter.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
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.
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.
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.