Avalanche Forecast
Regions: Waterton Lakes.
The weekend will be a good time to avoid avalanche terrain: A warm storm is approaching and forecast snowfall amounts range anywhere from 40-80cm with 120km/h winds beginning on Saturday.
Weather Forecast
A warm storm is incoming! Models are calling for anywhere between 40-60cm of snow beginning on Friday and ending Sunday night, with nuclear southwest winds, up to 120km/h at ridgetop on Saturday. Freezing levels will likely sit around 1500m, but some models have them as high as 1850m.
Snowpack Summary
A bit of fluff sits on a highly variable snowpack, and most areas have seen significant wind. The December 9 crust is down 30-80cm and is more prominent immediately around Cameron Lake, still giving hard sudden results in test profiles. A sandwich of crusts and facets form the base of the snowpack. Eastern areas hold a structurally weaker snowpack.
Avalanche Summary
No recent avalanches observed
Confidence
Intensity of incoming weather systems is uncertain
Avalanche Problems
Storm Slabs
The incoming new snow and high winds will form new slabs in most areas beginning on Saturday, and we expect to see a natural avalanche cycle. This will be a good time to avoid all avalanche terrain.
- Watch for fresh storm slabs on exposed lee slopes and open areas at all elevations.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 2
Persistent Slabs
Conflicted weather models are calling for anywhere between 40-80cm of snow, which could easily overload buried persistent weak layers and trigger large avalanches. This will be a good test of the snowpack, but not a good time to be in it.
- Avoid avalanche terrain during periods of heavy loading from new snow and wind.
- If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 2 - 3