Confidence
Fair - Intensity of incoming weather is uncertain on Wednesday
Weather Forecast
Synopsis: A ridge builds into the region Monday followed by a moderate system Tuesday night. A strong zonal flow sets up in the wake of the Tuesday night storm.Monday: Freezing Level: 1300m. Precip: 2/4mm – 2/6cm Wind: Light, SE.Tuesday: Freezing Level: 1600m Precip: 10/15mm – 10/25cm (overnight) Wind: Strong, SWWednesday: Freezing Level: 1800m Precip: Convective flurries. Wind: Light, South.
Avalanche Summary
No new avalanches reported Saturday. Previously, wet-loose avalanches up to Size 2.5 were running naturally on solar aspects when the sun was out.
Snowpack Summary
It's still winter up above 1700 or so. At upper elevations 15-25cm of new snow is covering a crust or wet snow. In some places in the alpine and at treeline this new snow may have buried a recently formed layer of surface hoar or facets. At lower elevations (below 1700m) rain has made the snow surface wet or moist. New snow combined with wind have made large cornices even bigger.The March 10th surface hoar/crust interface is buried more than 100cm in most places. Although unlikely to trigger, this deep persistent weakness remains a concern because of the potential for very large avalanches particularly with heavy triggers such as cornice falls or lighter triggers on solar aspects where the crust is more prevalent. Below this the snowpack is strong and well settled.
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.
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.