Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Little Yoho, Sunshine, West Side 93N.
The hazard rating is for the highest danger for the day.
The deterioration could happen fast with the forecasted warm temps, sunny skies in the morning, and light winds. Be mindful that snow is on the way and could start as early as the afternoon.
Start very early and finish early.
Confidence
Moderate
Avalanche Summary
Afternoon warming has produced numerous wet loose avalanches sizes 1-2 over the last several days. While activity may be tapering, there is still a high likelyhood for avalanches when the sun is shining and temperatures warm up in the afternoon.
On Saturday, there was a size 3 avalanche that failed on the deep persistent slab. The cornice that triggered the layer is a reminder that large loads have the potential to trigger these basal facets.
Snowpack Summary
Expect isothermal snow below 2100m. Surface crusts exist to ridge top on solar aspects. Dry snow can still be found high on due north aspects above 2400m.
The mid-pack Feb 3 persistent layer (facet layer) is still lingering on high northerly aspects, above 2500m. Basal facets and depth hoar remain a weak layer at the bottom of the snowpack at all elevations and aspects.
Weather Summary
Sat Evening: Wind southeast: 10 km/h. Freezing level 1900m.
Sunday: Mix of sun and clouds in the morning with 10-15 cm of snow expected to start in the late pm. Alpine High -2 °C, with light southerly winds.
Freezing level: 2600 m
Monday: Cloudy with sunny periods and isolated flurries. Alpine low -8 °C, high -5 °C. Winds out of the west @ 15 km/h.
Freezing level: 2400 m
For more detailed weather click here.
Terrain and Travel Advice
- Avoid exposure to overhead hazards when solar radiation is strong.
- Cornices become weak with daytime heating or solar exposure.
- Cornice failure may trigger large avalanches.
Avalanche Problems
Loose Wet
Loose wet and dry avalanche activity will likely increase with solar input and/or daytime warming.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Deep Persistent Slabs
Recent load with warming may be enough to reawaken this layer. Cornice failures will also be more likely and may trigger deeper layers. Deep persistent layers are difficult to forecast.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3