Strong winds, heavy precipitation and significant warming are creating dangerous avalanche conditions at upper elevations.
A hard crust with surface hoar or facets overtop is buried 40 to 100 cm deep. Storm slabs could step down to this layer, creating larger than expected avalanches.
30 to 45 cm of new snow is expected by Wednesday morning. Storm slabs will be most reactive in wind-loaded areas or in areas seeing rain for the first time.
Freezing levels are expected to rise to 1800 m. Wet loose avalanches will be most likely in areas where dry snow is being rained on for the first time.
It's been a stormy week with a significant natural avalanche cycle occurring, up to size 3. On Sunday, there were reports of size 1.5 to 2.5 slab avalanches.
With heavy precipitation, strong winds and warming in the forecast, both natural and human-triggered avalanches will be likely in the alpine.
Strong southwesterly winds and 30 to 45 mm of precipitation is expected to accumulate overnight through Wednesday morning, with freezing levels reaching 1600-1800m . The snow surface will be wet below the rain/snow line.
A hard crust with surface hoar or facets that formed on January 26th is buried 40 to 100 cm deep. Storm slabs could step down to this layer, creating large avalanches. Previous rain events may have neutralized this problem at lower elevations.
Treeline snow depths throughout the region range from 250 to 450 cm.
Tuesday Night
Cloudy. 20 to 30 mm of rain at treeline. 50 km/h south ridgetop wind. Treeline temperature 1 °C. Freezing level 1500 m.
Wednesday
Cloudy. 20 to 40 mm of rain at treeline. 70 km/h south ridgetop wind. Treeline temperature 2 °C. Freezing level 1800 m.
Thursday
Mostly cloudy. 10 to 15 mm of rain at treeline. 40 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 1800 m.
Friday
Mix of sun and clouds. 3 to 10 mm of rain at treeline. 60 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 1800 m.
More details can be found in the Mountain Weather Forecast.
