Avalanche Forecast
Issued: Nov 28th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
TRettie,
Avalanche Canada
The snow pack and avalanche hazard varies throughout the range. Read the complete forecast to get the details specific to your region.
Summary
Confidence
Low - Uncertainty is due to extremely variable snowpack conditions reported through the region.
Weather Forecast
Sunday night: the North half of the range will see freezing levels fall to 1000m with moderate West to Southwest winds. The South half of the range will see warmer temps and strong winds from the Southwest. Freezing levels will stay as high as 1600m. Up to 10mm throughout the range.
Monday: No precipitation during the day. The freezing level will be around 1600m throughout the range and winds will be moderate from the West.
Tuesday: Freezing levels will start around 1500m and rise to 2000m as another storm hits the range. 5 to 20mm of precipitation will fall in the evening with the largest amounts of precipitation in the Dogtooth range. winds will be strong from the Southwest.
Wednesday: The storm will reach its peak early in the morning. Freezing levels around 2000m and strong winds from the Southwest. Up to 15mm of precipitation with the largest amounts in the Dogtooth.
Avalanche Summary
On Sunday numerous natural avalanches up to size 2 were observed in the Toby creek drainage. These avalanches ran on a surface hoar layer believed to be widespread in this area above 1600m.Â
Several storm slab avalanches up to size 1.5 were observed in the North part of the range.
Snowpack Summary
Fresh wind slabs have been formed in the treeline and alpine. This hazard is greatest in the North half of the range. A surface hoar layer has been observed down 30 to 40cm in the Toby Creek drainage. A mid November rain crust is down 30 to 60cm and exists below 2100m.
Several early season crusts exist throughout the lower pack. A late October facet/crust layer sits at the bottom of the snowpack. it likely only exists above 1900m.
Average snowpack depth at treeline is 100 to 180cm with the deepest snow pack found around the Bugaboos.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
The wind slab hazard will be greatest in the Northern half of the range. Use extra caution on wind effected terrain in the alpine and treeline.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of Facets at the base of the snowpack from late October has been observed. We need more information on the distribution of this layer but we suspect it only exists at high treeline elevations and into the alpine.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Nov 29th, 2021 4:00PM
