Regions
Northwest Inland.
Confidence
Poor - Due to limited field observations
Weather Forecast
Synopsis: Precip should taper off by Wednesday morning. The trailing cold front brings freezing levels down to Valley Bottom with no significant precipitation expected. Colder temps and broken cloud cover should persist through Thursday evening before a weakening low makes landfall Thursday night, persisting through Friday.Wednesday: Freezing Level: Near valley bottom. Precip: Isolated convective flurries. Wind: Mod, SW.Thursday: Freezing Level: Valley bottom. 1800m Precip: Nil Wind: Mod, SWFriday: Freezing Level: 500m Precip: 5/10mm – 8 – 15cm Wind: Strong, SE.
Avalanche Summary
No new avalanche activity reported Monday. Natural and skier triggered loose wet sluffs were reported in steep sun-exposed terrain on Sunday. On Saturday, widespread loose dry sluffing was reported in steep terrain running on a recently buried crust.
Snowpack Summary
15-25 cm of new snow sits on a melt-freeze crust at most elevations. Warm temperature and solar radiation resulted in moist snow on solar aspects and lower elevations. A new surface crust may form before the next system arrives on Tuesday night. Pockets of wind slab have developed in exposed lee terrain and cross-loaded gullies. 30 - 60 cm of snow overlies a crust, old wind slabs or surface hoar layer buried on March 9th. The distribution of the surface hoar is also highly variable and it does not exist in every drainage. I would still remain cautious and continue to dig and test before diving into my line. Deeper in the snowpack, basal facets may resurface as a concern with continued mild temperatures.Cornices have become well-developed and could easily become unstable during periods of warm weather or direct solar radiation.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
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.