Conservative decision-making is essential following a period of intense warming.
A buried weak layer in the snowpack could produce very large avalanches.
Persistent slab avalanches are still possible after the period of warming. Continue with conservative terrain choices and assess the snow for instability caused by warming and sun.
Warm temperatures and the effect of the sun may trigger loose wet avalanches. The more the snow feels like a slushie, the more likely these avalanches.
These may step down to deeper layers resulting in larger-than-expected avalanches.
Large natural persistent slab avalanches (up to size 2.5) were reported on Friday. Pinwheeling and loose wet activity also occurred.
Over the last week, skiers were surprised by large avalanches; several were remotely triggered from a distance from low-angle or flat terrain. These avalanches failed on the buried weak layer described in the snowpack summary.
Expect a surface crust at most elevations. Where the snow still feels wet, or like a slushie, avalanches are more likely to still occur.
A layer of weak, faceted crystals over a crust, or surface hoar, is the primary layer of concern, buried around 40 to 80 cm deep. This layer has produced large avalanches, especially at treeline and below, during the last week.
Sunday Night
Increasing cloud. 40 to 50 km/h west ridgetop wind. Treeline temperatures 0 °C. Freezing level drops to 1000 m.
Monday
Partly cloudy. 20 to 30 km/h northwest ridgetop wind. Treeline temperatures +2 °C. Freezing level 1500 m.
Tuesday
Partly cloudy. 20 to 30 km/h east ridgetop wind. Treeline temperatures +2 °C. Freezing level 1500 m.
Wednesday
Cloudy with 5 to 10 cm of snow. 30 to 40 km/h east ridgetop wind. Treeline temperatures -1 °C. Freezing level 900 m.
More details can be found in the Mountain Weather Forecast.
