Pay attention to clues like cracking and whumphing, and avoid convexities to manage the current problems. We are bracing for a storm to arrive tonight, bringing up to 40mm in 24 hours with strong winds. If the forecast is right, things will get spicy
Summary
Weather Forecast
Today expect a mix of sun and cloud, alpine highs should rise to a balmy -12'C with light winds. Overnight the storm will arrive, with 7cm expected overnight. Thursday heavy snowfall will bring ~30cm, with freezing levels rising to 1500m, alpine highs of -4 and moderate to strong SW winds intensifying loading rates. Friday we expect another 10cm.
Snowpack Summary
Strong N'ly winds, combined with ~30cm of loose snow has reverse loaded slopes and formed wind slabs at ridgetop and immediate lees. The storm snow overlies a variety of surfaces; sun crust on steep solar slopes, hard windslabs in the alpine and gully features, small surface hoar and facets. As the storm slab develops it is unlikely to bond well.
Avalanche Summary
Strong N'ly winds triggered several size 2-2.5 natural avalanches along the highway corridor. They were primarily from steep paths with lee start zones, and avalanches ran well onto the fans. Skiers/riders have reported triggering slabs up to 60cm deep, with some remote triggering from up to 50m away. Propagation has been minimal in the soft slab.
Confidence
Intensity of incoming weather systems is uncertain
danyelle magnan,
Parks Canada
