Avoid wind-loaded areas at upper elevations. Recently formed wind slabs overlie a slick crust and could remain reactive to human triggering for longer than is typical.
Warm temperatures and solar radiation have the potential to rapidly increase avalanche danger. Watch for changing conditions with aspect, elevation, and time of day.
Strong southerly winds have redistributed 15 - 40 cm of recent snow into deep deposits of wind slabs at higher elevations. These wind slabs may remain reactive to human triggering, particularly where they overlie a slick crust.
This week, 15-40 cm of storm snow was accompanied by strong southwest winds, creating hard wind-affected surfaces in open areas, and wind slabs in lee terrain features. This new snow overlies a rain crust formed earlier in the week.
The mid-snowpack is well-settled. The lower snowpack consists of several crusts with weak faceted crystals above and below that are beginning to heal and bond to each other.
Snowpack depths are roughly 140 to 180 cm at treeline.
On Saturday, many riders got surprised by small (size 1) reactive wind slabs failing on the underlying rain crust. These slabs occurred in wind-loaded terrain in the alpine and treeline.
Looking forward to Monday, wind slabs may remain reactive to human triggering for longer than is typical due to the slick crust they are sitting on. Avoid wind-loaded terrain and watch for signs of instability as you travel.
Please continue to post your observations and photos to the Mountain Information Network.
Sunday night
Clear with cloudy periods. Alpine temperatures drop to a low of -5 °C. Light ridge wind. Freezing level at valley bottom.
Monday
Sunny with cloudy periods. Alpine temperatures reach a high of -2 °C. Ridge wind light to 15 km/h. Freezing level rises to 1800 metres.
TuesdayA mix of sun and cloud. Alpine temperatures reach a high of -3 °C. Mostly light ridge wind occasionally gusting to 35 km/h from the southwest. Freezing levels rise to 400 metres.
WednesdayA mix of sun and cloud. Alpine temperatures reach a high of -3 °C. Ridge wind light to 25 km/h from the south. Freezing level rises to 700 metres.
More details can be found in the Mountain Weather Forecast.
