The main thing to look out for is newly-formed wind slabs from increasing and variable wind along with some new snow on Monday.
Shifting wind may form wind slabs on all aspects. The wind was first from the northwest this weekend but is forecast to shift to the south or southwest on Sunday and Monday. Monday's snowfall and strong wind is expected to form new wind slabs in exposed terrain.
SATURDAY NIGHT: Mostly cloudy, 20 km/h south wind, alpine temperature -10 C.
SUNDAY: Mostly cloudy, 20 to 40 km/h south wind, alpine temperature -10 C.
MONDAY: Cloudy with snowfall, accumulation 5 to 10 cm, 40 to 60 km/h southwest wind, alpine temperature -10 C.
TUESDAY: Cloudy with light snowfall, accumulation 5 cm, 20 km/h southeast wind, alpine temperature -11 C.
A MIN report from Wednesday shows some small wind slab avalanches on northeast slopes in the Tutshi area. This activity is indicative of the type of avalanches that are possible this weekend, although with shifting winds they are now possible on all aspects.
Soft snow can be found in sheltered terrain whereas hardened wind slabs are likely found in the alpine and exposed treeline. An increasing wind speed trend on Sunday into Monday may allow for further formation of wind slabs, particularly with some new snowfall on Monday. Below this surface snow lies a widespread melt-freeze crust. The crust has been reported up to 1400 m in the Wheaton Valley, up to 1800 m near the Alaska border, but was not evident between 1400-1700 m in the Tutshi area. The main concern is newly-formed wind slabs sitting on this crust.
The lower snowpack is generally settled and strong after a massive storm at the beginning of December. However, there is potential for weak snow at the bottom of the snowpack in colder drier areas such as the Wheaton Valley. We have minimal data from these areas, but recommend extra caution around shallow rocky slopes in thinner snowpack areas.
