Avalanche Forecast

Fair

Wednesday: Mostly clear with valley cloud possible in the morning. A temperature inversion is expected to bring treeline and alpine temperatures above freezing, while lower elevations should stay cold. Winds should be light to moderate from the northwest. Thursday: Low cloud in the morning changing to a mix of sun and cloud throughout the day as the temperature inversion weakens and lower elevations start to warm up with freezing levels as high as 2500m. Light to moderate northwesterly winds shifting to westerlies in the afternoon. Friday: A mix of sun and cloud and dry throughout the day. Freezing levels remaining at around 2500m.

Recent observations include snowballing and several wet loose sluffs ip to Size 1.5 on sun-exposed slopes. A few large slab avalanches up to Size 3, involving the persistent weakness buried at the beginning of January also released due to intense warming on south aspects on Monday. Check out this incident report from the Duffey Lake area on the weekend. The 60cm deep slab avalanche may have release on the surface hoar persistent weakness buried at the beginning of the month.

Above freezing temperatures at higher elevations caused snow surface moistening on on sun-exposed slopes, breaking down the 1-2cm surface crust, and weakening wind slabs. The surface snow on northerly aspects has been remaining dry with continued surface hoar growth. Below this, 40-80 cm of settling storm snow sits on a persistent weakness of buried surface hoar, facetted snow, and /or a crust. Recent snowpack tests show that this interface is gaining strength but is likely still susceptible to human triggering with potential to propagate widely. No significant weaknesses have been reported recently below this in the mid snowpack layers. Near the base of the snowpack, a crust/facet layer exists, which is now unlikely to be triggered, except perhaps by heavy triggers in steep, shallow, rocky terrain where more facetting has taken place.