The new snow and strong wind is expected to form new wind slabs that will bury the rain crust. If more than around 30 cm of snow accumulates in your riding area, a more widespread storm slab problem may develop and local hazard could be High.
Confidence
Low - Due to the number of field observations
Weather Forecast
Light to moderate snowfall is expected Wednesday overnight and for most of the day on Thursday. 10-15 cm is expected overnight with another 15-20 cm during the day. Freezing levels are expected to be around 600 m early Thursday morning and reach around 1000 m in the afternoon. Alpine wind is forecast to be moderate to strong from the southwest for most of the day. Snowfall is forecast to continue Thursday overnight and during the day on Friday with the current forecast for another 15-30 cm. Freezing levels are forecast to remain below 1200 m during this period and alpine wind should remain moderate to strong from the south and southwest. The last significant storm pulse is currently forecast for Saturday with 20-30 mm currently forecast during the day and freezing levels reaching around 1500 m.
Avalanche Summary
No new avalanches have been reported recently but observations have been very limited during the warm storm. On Thursday, the new snow will bury the widespread surface crust and is expected to form new wind slabs in exposed terrain. At lower elevations, rain may result in wet sluffing from steep terrain features.
Snowpack Summary
Heavy rain has saturated the upper snowpack well into the alpine. As temperatures drop, a widespread crust layer is expected to form. New snow on Thursday will bury this crust and strong alpine wind is expected to form wind slabs.The late February weak layer is now down 1.5 m or more in the snowpack and is now expected to have become unreactive. This layer is composed of a sun crust on southerly aspects and surface hoar on shaded aspects. The snowpack is generally well settled and strong below this layer.
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.