If the snowfall exceeds the forecast amounts, HIGH danger may be possible. Stay locally aware.
Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
Expect precip to ramp up overnight and into Thursday morning, with as much as 20cm of new snow and strong southerly winds. The freezing level should fall overnight then reach a maximum of 1300m. Friday / Saturday: Precipitation should taper dramatically and the sun will poke out again, with winds turning from southerly to westerly. Freezing levels will fall as the flow turns, bringing more seasonal temperatures.
Avalanche Summary
Loose wet avalanches up to size 2.0 triggered by daytime heating have been reported at lower elevations, as well as isolated cornice releases in the high alpine to size 2.0 that did not release deeper layers. Small windslab events have also occurred on lee and cross loaded terrain features.
Snowpack Summary
Above 1700m, up to 20cm of new snow now overlies the March 26 interface. This has been accompanied by consistently moderate and at times gusty southwesterly winds forming windslabs in lee locations. Cornices are huge, and will continue to grow with this weather pattern. The March 26 interface is a crust on all aspects except true north treeline and alpine, where small surface hoar (5mm) is present in sheltered places. At lower elevations, the surface snow has had less recovery and the upper snowpack is predominantly moist. Below the newest storm interface, last week's storm snow is well settled and bonded. The deep, persistent early February layers linger in the snowpack and remain a concern with heavy 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.
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.