Avalanche Forecast
Issued: Nov 18th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Storm Slabs.
Cory Boschman,
Natural avalanche activity has tapered off, but be conservative. There is still concern for human triggering.
Summary
Weather Forecast
Friday. Cloudy with sunny periods. Precipitation: Nil. High -9 °C. Ridge wind west: 15-35 km/h.
Saturday. Flurries. Accumulation: 6 cm. Low -12 °C, High -10 °C. Ridge wind west: 20 km/h gusting to 60 km/h.
Sunday. Mainly cloudy with isolated flurries. Precipitation: Trace. Low -12 °C, High -9 °C. Ridge wind southwest: 20 km/h.
Snowpack Summary
The 60-80cm of storm snow that fell over the past week continues to settle, and be redistributed by moderate southerly winds at ridge tops. This storm snow overlies variable basal snowpack depending on aspect and elevation with a melt freeze crust up to around 2500m, and weak faceted snow near the ground in most places tree-line and above.
Avalanche Summary
With good visibility on Wednesday numerous avalanches, up to size 3.5, were observed. Most occurred during and near the end of the past storm. These avalanches were predominantly out of steep alpine features, but a large avalanche was caused by explosives in a similar terrain feature at tree-line, propagating over 800m wide.
Confidence
Due to the number of field observations
Problems
Wind Slabs
Watch for new wind loading at ridge tops and in the alpine as moderate SW winds are in the forecast and there is a lot of snow available for transport.
- Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.
- Use caution in lee areas. Recent wind loading have created wind slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Storm Slabs
Storm slabs are settling down but use caution and dig down to test the snow before committing to a slope.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 19th, 2021 4:00PM
