Avalanche hazard will gradually rise over the day and into Tuesday night as new snow and wind form fresh wind slabs at upper elevations.
If you see more than 20 cm by the end of the day, treat avalanche danger as CONSIDERABLE at elevations with wind blowing the snow around.
New snow and strong winds are likely forming fresh wind slabs in leeward terrain features at upper elevations.
Cornices have also been growing. A cornice fall is a large load that can trigger avalanches on the slope below.
A couple of weak layers exist in the mid snowpack, buried 40-80 cm and 90-150 cm below the surface. They are highly variable in form and distribution and there has not been any associated avalanche activity in the last few days. Incoming snowfall in the forecast for this week will add additional load to these layers and may shed some light on whether they will remain a concern.
Monday night: Snow, up to 5 cm, moderate to strong southwest wind, freezing level 500 m.
Tuesday: Snow, 5-15 cm, strong southwest wind, alpine high -4, freezing level 1400 m.
Wednesday: Snow overnight 10-20 cm then clearing, strong southwest wind easing to moderate, alpine high -7, freezing level 1200 m.
Thursday: Sunny, light northwest wind, alpine high -7, freezing level 700 m with a weak inversion setting up.
Explosive work on Monday produced wind slabs up to size 1.5. Explosive cornice control work conducted on Saturday produced a size 1.5 cornice which did not trigger a heavily skied slope below, and a vehicle-triggered cornice drop tested a north facing alpine slope below, triggering a size 2 wind slab which did not step down to deeper layers.
Small amounts of new snow fall on wind affected surfaces at upper elevations, surface hoar in wind sheltered areas and a thin crust on solar aspects. Winds are likely redistributing new snow into wind slabs and growing cornices.
A couple of persistent weak layers exist in the upper to mid snowpack:
Avalanche activity on these layers has dwindled since last week and snowpack tests results have been moderate to hard planar, but not showing propagation. Incoming snowfall in the forecast for this week will add additional load to these layers and may shed some light on whether they will remain a concern.
