Heightened avalanche conditions exist in specific terrain features where weak layers in the upper snowpack are possible to human-trigger.
Continually assess conditions as you travel.
Recent snow and wind have formed wind slabs in leeward terrain features at upper elevations. They may be especially reactive where they sit over a slippery crust.
A weak layer of surface hoar/crust/facets exists in the top 30 cm of the snowpack. It will be most sensitive to triggering in northerly upper elevation lees where the overlying snow is deepest and not capped by a more recent crust.
On Sunday, explosive control work in the alpine produced a few cornice results and several persistent slab avalanches size 1 to 1.5, failing on the January weak layer described in the snowpack summary.
In the past week, human-triggered persistent slab avalanches on this layer were reported size 1 to 1.5, most occurring at treeline and above.
Roughly 10 to 15 cm of wind affected new snow overlies a widespread variable crust on all but high alpine north facing terrain.
A weak layer of surface hoar on a melt-freeze crust, with a thick layer of facets below, formed in late January is buried 20 to 50 cm deep. This well developed layer is expected to become increasingly problematic as they get buried deeper.
The mid and lower snowpack remain well settled, with no significant concerns at this time.
Monday Night
Mostly cloudy. 1 cm of snow. 40 km/h west ridgetop wind. Treeline temperature -7 °C.
Tuesday
Mostly cloudy. 30 km/h west ridgetop wind. Treeline temperature -7 °C.
Wednesday
Sunny. 20 km/h west ridgetop wind. Treeline temperature -6 °C.
Thursday
Mostly sunny. 40 km/h west ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
