Issued: Apr 9th, 2023 4:00PM
The alpine rating is Wind Slabs and Persistent Slabs., the treeline rating is , and the below treeline rating is Known problems include
Watch for fresh and reactive wind slabs forming where recent soft snow is available for transport. Seek out wind-sheltered terrain for the best turns.
On Saturday a rider triggered a cornice fall from a distance, which produced a size 3 persistent slab avalanche on a northeast aspect at 1750 m. The avalanche was 200 cm deep and was suspected of having failed on the layer of facets above a crust buried in January.
On Friday a size 1 skier remote was reported on a north east facing slope at treeline. The avalanche was 40 cm deep and failed on a weak interface, possibly also a layer buried in January.
20-30 cm of recent soft snow may have seen some redistribution by recent wind but above 1200 m, it remains largely available for wind transport. Below 1200 m, moist snow or a thin crust may exist at or near the surface.
The new snow sits over previously wind-affected snow on north and east facing slopes and a crust on south facing slopes.
A weak layer of surface hoar/crust/facets buried in early January is now buried over 1 m deep in most areas. This layer has produced recent avalanche activity and remains a concern in terrain where the snowpack is thin. The lower snowpack consists of basal facets, particularly in shallow areas.
Cloudy with 5-10 cm of new snow. Moderate to strong southerly winds. Alpine low -8 C.
A mix of sun and cloud with isolated flurries possible. Moderate southwest winds. Alpine high -7 C.
Mostly sunny. Light southwest winds. Alpine high -5 C.
A mix of sun and cloud. Moderate to strong southwest winds. Alpine high -7 C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Use caution on large alpine slopes, especially around thin areas that may propagate to deeper instabilities.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
South to southwesterly wind likely continues to transport recent snow into wind slabs. These wind slabs may be thin and isolated but ill likely be reactive to human triggers.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
A layer of facets sitting on a crust buried in January has recently been reactive. Triggering is most likely in areas where the snowpack is thin and weak, or with a heavy load like a cornice fall or the weight of a smaller avalanche in motion triggering this deeper layer.
Aspects: All aspects.
Valid until: Apr 10th, 2023 4:00PM