Danger will elevate throughout the day as slopes warm up. Plan your day around avoiding cornices and sun-exposed slopes. Read more in this Forecasters' Blog.
Lingering wind slabs formed by 10-20 cm of recent snow and previously strong winds from shifting directions may remain reactive on lee features in the alpine.
Cornices are large and looming along many ridgelines and have likely grown with the recent wind. Strong solar radiation and warming are common triggers for cornice failures which could trigger avalanches on the slopes below.
Small wet loose avalanches may start to run naturally on steep solar aspects when the sun comes out.
MONDAY NIGHT: Mostly cloudy skies, 30 km/h southwest wind, freezing level around 1200 m with treeline temperatures around -2 C.
TUESDAY: Mix of sun and cloud, 20 km/h southwest wind, freezing level climbs from 1200 to 1900 m throughout the day, treeline temperatures climb to +1 C.
WEDNESDAY: Sunny, light wind, freezing level climbs from 2000 to 2700 m throughout the day, treeline temperatures climb to +5 C.
THURSDAY: Sunny, light wind, freezing level steady around 2800 m, treeline temperatures around +5 C.
Warm sunny weather this week will likely cause wet loose avalanches on sun-exposed slopes and large cornice falls. After several days of warm weather natural slab avalanches will become a concern.
There were many small (size 1) wet loose avalanches on south-facing slopes at all elevations on Sunday and a few size 2 cornice failures on north and east facing slopes. On Saturday there were a few naturally triggered wind slab avalanches (up to size 2) on northeasterly aspects in the alpine.
Sunny skies and rising freezing levels will result in melting surfaces on solar aspects and lower elevations. 5-20 cm of snow is quickly settling and strengthening, although some wind slabs could linger at upper elevations. The recent snow has covered a variety of snow surfaces, including wind affected snow, crusts on solar aspects and at lower elevations, and soft snow on sheltered slopes at upper elevations.
The lower snowpack is reported as well settled and strong in most areas. However, weak facets exist at the base of the snowpack in the more shallow snowpack zones across the region. Where it exists, this layer has the potential to be triggered on steep, rocky slopes with a shallow or thin to thick snowpack; especially with large loads such as a cornice fall.
Cornices are large, looming, and capable of triggering large avalanches when they fail.
