Avalanche Forecast
Issued: Nov 18th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
Parks Canada/Parcs Canada,
Avalanche Canada
Wind slabs remain the primary avalanche concern. Wind and new snow on Sunday created wind slabs at upper elevations that are still possible to trigger. Though small in size, these slabs could pose serious consequences if triggered in the wrong terrain.
Not much snow at the lower levels of treeline or below; it is Early Season!
Summary
Confidence
Moderate
Avalanche Summary
Local ski hills were able to trigger wind slabs as well as slabs on the basal crust from size 1-1.5 with explosives on Monday.
On Sunday local ski hills reported several small windslabs and a recreational party reported a remotely triggered wind slab while ascending a couloir near Bow Summit.
Our field team reported numerous whumpfs while touring in the Sunshine area on Monday. These are likely failing on one of the buried crusts in the snowpack.
Snowpack Summary
A few cms of snow over previous wind slabs in exposed alpine and treeline terrain. In the middle of the snowpack the Nov 9 solar/temp crust is present. In some places there is surface hoar on this crust making it more reactive to loading. At the base of the snowpack a crust that formed in late October can be found to ridgetop. Facets are developing around this basal crust. Treeline snow depths range from 40-60 cm with less snow at lower elevations and many thinly buried hazards.
Weather Summary
A mix of sun and cloud with no new snow on Tuesday and only a few cm's expected on Wednesday. Winds remain light from the SW on Tuesday until late in the afternoon when they increase to the moderate-strong range from the south. A cooling trend continues, with forecast lows reaching -20°C in the alpine.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
A bit of new snow (5-10 cm) and consistent, strong S-SW winds over the past 48 hours have created wind slabs in the alpine and at treeline. We expect it will be possible to trigger these slabs in lee loaded areas. There is also concern for these to step down to the buried crust layers in the snowpack.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 19th, 2024 4:00PM
