Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Little Yoho, Sunshine, West Side 93N.
The hot weather will continue through the week, with alpine temperatures reaching +15 and freezing levels to 4000 m. Avoid all avalanche terrain. Backcountry conditions are poor and will not improve until it cools later this week. Hikers and scramblers: avoid all avalanche terrain.
Confidence
High
Avalanche Summary
A widespread natural avalanche cycle to size 4 continues with avalanches failing on the ground level on all aspects and elevations, many running to the valley bottom. This is the biggest avalanche cycle of the season. Click the link's for recent avalanche info on the Plain of Six Glaciers and Lake Louise area.
Snowpack Summary
The heat has penetrated the snowpack and destabilized it at all elevations. Warm temperatures overnight will prevent any refreezing. This will persist for the remainder of this week. Expect wet snow on all solar aspects and unsupportive isothermal snow (slush) at lower elevations. Widespread avalanches are failing on the ground.
Weather Summary
A ridge of high pressure will continue to dominate the region over the next few days bringing unseasonably hot weather, sunny skies and light winds. Freezing levels may reach 4000 m. Clouds and cooling should arrive by next weekend.
Terrain and Travel Advice
- Avoid all avalanche terrain during periods of intense solar radiation.
- Avoid exposure to overhead avalanche terrain as temperatures increase.
Avalanche Problems
Deep Persistent Slabs
We are seeing lots of avalanche activity on the weak facets and depth hoar at the bottom of the snowpack as the upper snowpack heats up and looses cohesion. These avalanches are easily triggered, often large and running long distances.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Very Likely - Certain
Expected Size: 2 - 3.5
Cornices
With the high freezing levels and direct sun exposure, the mountains will begin to shed. Do not expose yourself to any corniced features or steep slopes below cornices as the day heats up.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Certain
Expected Size: 1.5 - 2.5
Loose Wet
We expect wet slabs and wet loose avalanches on all aspects and elevations, especially when the sun cooks the slopes. Slush and wet snow will run like water down gullies and through rock bands: the spring melt is on.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Certain
Expected Size: 1 - 2.5