20-30 cm thick storm slabs formed earlier in the week may continue to be reactive to human triggers in isolated locations at upper elevations.
Minimize exposure to sun-exposed slopes when the solar radiation is strong.
20-30 cm thick storm slabs formed earlier in the week may continue to be reactive to human triggers in isolated locations at upper elevations.
A weak layer of facets exists near the base of the snowpack. The likelihood of human triggering is low given the layer's depth, but large triggers such as cornice failures or smaller avalanches in motion have the potential to produce very large avalanches with surprisingly wide propagation. Suspect terrain for human triggering includes steep, shallow, and rocky terrain where the snowpack transitions from thin to thick.
A naturally triggered size 2.5 wet loose avalanche was reported on a southwest aspect in the alpine near Valemount on Friday.
Expect to find a melt-freeze crust on the surface of all aspects at treeline and below and on sunny aspects in the alpine. Solar radiation will break down the crust on sunny slopes throughout the day.
Strong solar radiation has settled the 20-30 cm of recent snow into a storm slab which may remain reactive to human triggers in isolated locations at upper elevations.
Strong south wind during the storm earlier in the week added to slab formation on lee aspects at treeline and above.
The recent snow is sitting on a variety of surfaces. These include sun crust on sunny aspects and surface hoar (3-10 mm) on some shady and sheltered slopes.
The mid-snowpack is generally strong but the lower snowpack is a different story..
The November facets are still prominent at the base of the snowpack. They are showing signs of improving but this layer remains a significant concern in rocky, shallow, or thin to thick snowpack areas at treeline and above.
Saturday Night
Clear skies / 10 km/h southeast ridgetop wind / Temperature at treeline around -10 C / Freezing level valley bottom
Sunday
Sunny / 20 km/h east ridgetop wind / Temperature at treeline around -3 C / Freezing level 1700 m
Monday
Sunny / 10 km/h northeast ridgetop wind / Temperature at treeline around -2 C / Freezing level 1800 m
Tuesday
Sunny / 10 km/h northeast ridgetop wind / Temperature at treeline around -5 C / Freezing level 1500 m
More details can be found in the Mountain Weather Forecast.
