Avalanche Forecast
Regions: Little Yoho.
New snow, mild temperatures and strong winds have increased the avalanche hazard!
Natural avalanches are possible and human triggering remains likely. Depending on how the weather forecast plays out we could see the hazard reach HIGH in some areas Monday.
Limit your exposure to avalanche terrain to manage this scenario.
Confidence
Moderate
Avalanche Summary
A small natural cycle up to size 2 was observed in the backcountry at treeline and above though visibility was limited.
Ski hills were able to trigger wind/storm slabs with ski cuts and explosives up to size 2 with failures in the new snow and on the facets under the new snow.
In the Banff area a skier accidental size 2 wind slab that likely propagated on the facets under the storm snow, occurred on Twin Cairns with one person going for a rocky ride but ending up relatively unscathed.
Snowpack Summary
10-30 cm of new snow has fallen with mild temps and strong S-SW winds helping to form new wind and storm slabs. This new snow sits over a layer of weak facets, surface hoar or sun crust from the past few dry cold weeks.
The mid and lower snowpack is mostly well-settled, though it is heavily facetted in thin snowpack areas. Tree-line snow depths range from 120 cm to 180 cm.
Weather Summary
A front will come through Sunday night, bringing anywhere from light flurries to 5-10 cm of new snow. Moderate to strong SW winds continue in the alpine through Monday. Freezing levels will drop to the valley bottom overnight and climb to 1800 m during the day.
Terrain and Travel Advice
- Make conservative terrain choices and avoid overhead hazard.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Loose avalanches may step down to deeper layers, resulting in larger avalanches.
Avalanche Problems
Storm Slabs
10-30 cm of new snow and strong S-SW winds have loaded lees areas at treeline and above with new slabs up to 60 cm deep. This is sitting on a weak layer of facets, surface hoar or sun crust. Human triggering will remain likely in steep or wind loaded terrain for the next few days.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5
Loose Dry
Wind speeds will stay elevated through Monday and will be moving snow at higher elevations. This will result in loose dry avalanches in steep terrain. With the facets under the new snow, these avalanches could run quite far. At low elevations we may also see loose wet avalanches due to warming.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 2