Avalanche Forecast

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Unsettled weather overnight with light precipitation, overcast skies, and light southwest winds. Some chance of broken skies on Saturday with freezing levels dropping to about 300 metres. The next storm is expected to slide down the coast from the northwest on Sunday. Most precipitation should be contained to near coastal areas, until Monday when a stronger low pressure system moves on-shore.

Ski cutting north of Stewart on Wednesday produced up to size 1.5 avalanches in the recent storm snow. The slabs were typically 20cm thick and failing on a layer of surface hoar that was buried on Tuesday. Buried surface hoar and wind loaded features are expected to be the main concerns right now but due to the lack of regular observations, we cannot yet issue avalanche problems or danger ratings for the region. If you are out in the mountains, please send us your observations and help us improve the forecast.

Early season snowpack observations are still limited in the region but there is enough snow for avalanches above around 1000-1200m. The average snowpack depth at treeline is reported to be around 1m and there are reports of over 1.5m of snow in the alpine. Surface snow tends to be variable with low density powder in sheltered areas, wind affected snow in exposed areas, and moist or wet snow at lower elevations. Recent strong southwest winds have likely formed wind slabs in leeward features at higher elevations. Buried surface hoar crystals from the middle of November up to 10mm have been found down 50-70cm in the south of region. A more recent surface hoar layer that was buried on Tuesday is reported to be up to 5mm in the area north of Stewart. Due to a lack of observations, there is a lot of uncertainty surrounding the distribution and persistence of these layers and it is best to dig down and test these layers before committing to big slopes. The mid and lower snowpack is generally moist to ground with a series of crusts.