Avoid avalanche terrain.
A natural avalanche cycle has started and is expected to continue for a few days.
Avalanches will be large and may run full path.
Multiple weak layers, buried up to 2.5 m deep, continue to produce surprising avalanches . Avalanches failing on these layers have been large and destructive.
Natural storm slabs could initiate at high elevations and run below treeline. These large avalanches could also step down to buried weak layers, resulting in very large avalanches.
Wet loose avalanches will increase in size and likelihood where precipitation falls as rain.
On Monday a natural storm slab avalanche cycle began. Avalanches occurred on all aspects and elevations. Most of the avalanches that were reported were size 2 to 2.5.
Over the weekend several size 3 and 3.5 persistent slab avalanches were reported. These avalanches were triggered naturally, remotely, and by falling cornices. They occurred on easterly aspects at treeline and above.
Ongoing rain will saturate the upper snowpack below treeline . At treeline and above, 50 to 100 cm of storm snow will continue to be redistributed by strong southwest wind, forming deep deposits on north and east aspects. A thick crust from earlier this month can be found down 70 to 120 cm at treeline and below.
Three concerning weak layers of surface hoar, facets and/or crust that formed in January and February are found down 100 to 250 cm deep.
The lower snowpack is well settled and bonded.
Tuesday Night
Cloudy. 10 to 20 cm of snow at treeline, rain at lower elevations. 50 km/h southwest ridgetop wind. Treeline temperature 1 °C. Freezing level 2200 m.
Wednesday
Cloudy. 5 to 20 cm of snow at treeline, rain at lower elevations. 50 km/h southwest ridgetop wind. Treeline temperature 2°C. Freezing level 2400 m.
Thursday
Cloudy. 10 to 25 mm of rain at treeline, snow in the alpine. 60 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 2400 m.
Friday
Mostly cloudy. 10 to 30 mm of rain at treeline, snow in the alpine. 60 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 2400 m.
More details can be found in the Mountain Weather Forecast.
