Clear skies and warm temperatures are forecast over the next few days. The March sun is strong and will pack a punch on solar aspects. Steep, rocky terrain will be the most susceptible.
Sustained strong winds from the SW have blown the available snow into wind slabs in open areas. These could be quite deep in immediate lee areas. Test sensitivity on small slopes with no consequence and extrapolate to the bigger terrain.
Deep persistent slabs are best managed by:
Cornices are best managed by:
A ridge of high pressure will bring mainly sunny skies, rising temperatures and 30-60km/hr winds from the South West. The freezing level is expected to rise to ~2100m on Thursday with valley bottom temperatures reaching +10. Some snow expected Friday evening into Saturday.
Strong SW winds have scoured exposed slopes and formed wind slab in alpine lee areas and open tree line slopes. In the Little Yoho Valley, the height of snow at tree line is ~280cm and does not have the same Persistent Slab problem as Banff and Kootenay.
Sunny skies and warm temperatures will have an effect on solar aspects, triggering loose wet avalanches. Avoid sun exposed slopes if the solar heating is intense, or the snow is becoming moist and mushy.
Two close calls in the Simpson area of Kootenay Park last weekend. South aspect at treeline and below treeline in the burnt forest is the pattern.