Approach solar aspects with caution as the March sun packs a punch and can start to destabilize the snow in as little as 30 minutes.
Watch for wind slabs in immediate lees along ridgelines and in gullied terrain, especially at higher elevations.
Avoid exposure to large features as the deep persistent slab can be triggered with solar radiation. The alpine is still variable in total amounts of snow but the basal layers haven't changed. The entire lower half is either facets or depth hoar.
No new avalanches have been reported in the last 24 hours.
Read on regarding a weekend incident involving a sun exposed slope: On Saturday skiers triggered a size 2.5/3 avalanche on a sun exposed slope near Mt Birdwood. This avalanche failed as the third skier crossed the slope and was triggered before the sun crust had started to break down. The slab was 30 to 80cm deep, failing on facets. Further details can be found on the MIN.
The fresh snow from last week has largely escaped the wind.....so far. Many areas still have soft snow, but expect sun crusts on solar aspects at all elevations where the terrain is steeper than about 20 degrees. The strong late March sun is melting these surface crusts and destabilizing the slopes. There are previously formed wind slabs in alpine areas, so keep an eye out for these in lee and cross-loaded features. The midpack remains highly variable with areas of more than 100cm of total snowpack being supportive, but in shallower areas ski penetration can still be to ground. The good old facets and depth hoar still lurk at the bottom of the snowpack and present an ongoing concern for full-depth avalanches. Expect the avalanche hazard to deteriorate throughout the day with the solar input and rising freezing level. This will be of greatest concern under larger features where the solar radiation could trigger the deep persistent layer.
Tuesday will bring sunny skies and light NW winds. The morning will start off cold at -18c in the alpine and warm up to -2c in the afternoon. Freezing levels are expected around 2100m.
More details can be found in the Mountain Weather Forecast.
