Avalanche Forecast

Fair - Timing, track, or intensity of incoming weather is uncertain on Tuesday

Tuesday: A strong westerly flow is expected across the interior today, accompanied by moderate snow amounts 10-15cms. Ridgetop winds will be SW-W blowing up to 100km/hr. Freezing levels 700-1000m. Wednesday: A second system will cross the Boundary bringing snow amounts up to 10cms. Freezing levels may climb to 1200m in the most Southern parts of the region. Ridgetop winds will ease off to 50km/hr or less. Thursday: Snow amounts near 5cms in the morning. Mainly dry conditions in the afternoon.

Sunday saw several natural small size 1-2 avalanches on all aspects, and explosive avalanche control produced size 1-2.5 on SE-SW aspects. On Saturday in the Bonnington Range several avalanche incidents occurred. The first reported was remotely triggered by a skier, it produced a size 3 slab avalanche from ridgetop. This slide was at 2200m on a North-North East aspect and ran 400m in length. There was also a skier remote size 2 from the same group. There were no involvements with these avalanches. Another group of skiers had similar observations from this mountain range. They triggered a skier remote size 3 from 100m away, additionally a size 2 sympathetic occurred. The size 3 crown depth was 50-120cms, 200m wide, and ran 400m. Both avalanches initiated from 1800m on S-SE aspects. The suspect layer possibly being the Mid December surface hoar/facet layer. This is a good indicator to be aware of the sensitivity in your local snowpack, and make observations while you travel. With forecast snow, wind and rising freezing levels the avalanche danger will be on the rise.

Over the weekend up to 35cms of new snow fell. This new snow came in denser that the previous, cold storm. This has formed storm slabs at all elevations, and wind slabs in the alpine. These slabs are reported to be quite reactive due to their poor bond on the cold snow interface below. The second layer of concern is a crust that lies down 50-60cms and exists below 1900m. The bond with this crust appears to be quite good, however, on steep slopes this could easily act as a weak interface, potentially creating a layer for avalanches that initiate in the upper snow to step down to. This will be a layer to watch with more snow load and rising freezing levels on Tuesday-Wednesday. Layers of concern deeper in the snowpack include a surface hoar/facet layer from mid-December and weak basal facets at the base of the snowpack in shallow snow areas. These layers have become less of a concern in the vast majority of locations. Snowpack depths in the region are around 240 cm.