Steep solar aspects could see increase natural avalanche activity this weekend as clear skies and warmer temps heat southerly aspects.
Be mindful of overhead avalanche hazard, especial on solar aspects.
Recent winds have produced wind-slabs in the alpine and some tree-line locations. With strong to extreme wind values forecasted for Sunday this avalanche problem could be come more reactive. Watch for active loading and new slab development.
This problem represents both the Dec. 2nd crust/ facet layer (treeline and below) and layers of faceted snow that were formed during the late December cold snap (all elevations). This is primarily an issue in shallower snowpack areas.
The ridge of high pressure will begin to break down on Sunday with winds becoming more westerly at ridge top. Peak wind values at ridge crest will be in the strong to extreme range through the day. Temperatures will be warmer with freezing levels near 1500m. Steep, sheltered South aspects will likely see increased warming due to solar heating.
Recent wind and new snow have created fresh wind slabs in the alpine and some tree-line areas. The new snow overlie facets in many places resulting in wide propagations in recent avalanches. The Dec. 2 crust and facets are generally 100-150cm deep producing hard to no results. Snow depth at tree-line is around 200-250 cm.
No new avalanches observed or reported Saturday. Avalanche control in Yoho last week produced slabs with every shot. Most were failing on a windslab or facet layer 40-60cm deep and then entraining facets in the track. One stepped down to the November facets ~ 180 cm deep.
