Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Little Yoho, Sunshine, West Side 93N.
Overall, the avalanche hazard will be lower in the morning and increase with daytime heating over the next few days.
Start early and finish early to take advantage of the lower hazard.
Click the following link for more info on spring conditions.
Confidence
High
Avalanche Summary
A quieter day for avalanches on Monday due to cloudy skies and slightly cooler temperatures.
Over the past few days, there have been lots of small wet loose avalanches and some cornice failures up to size 2 as temperatures heated up in the afternoon and the surface crusts broke down.
One skier triggered size 2.5 slab was reported in Kananaskis on Saturday during the heat of the day, and a couple of cornice triggered slabs up to size 2 have also been seen during hot afternoons.
Snowpack Summary
Surface crusts exist to ridgetop on solar aspects, and on all aspects to around 2400 m.
Due north alpine slopes still hold 5-15 cm of dry snow over firmer surfaces.
Below the settled mid-pack, shallow snowpack areas to the east have weak facets and depth hoar in the lower half, while deeper snowpack areas to the west have a well-settled lower snowpack.
Weather Summary
Monday night - Freezing levels dropping to 1500 m, scattered flurries and light NW winds. Treeline temperatures down to -4°C.
Tuesday - Mainly cloudy, light to moderate W winds, treeline temperatures up to +2°C with freezing levels rising to 2500 m.
Wednesday - Mainly cloudy, moderate W winds, freezing levels down to 2100m and rising to 2500 m. Treeline temperatures between -1°C and +1°C.
Terrain and Travel Advice
- Start your day early and be out of avalanche terrain during the heat of the day.
- The more the snowpack warms up and weakens, the more conservative your terrain selection should be.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
Avalanche Problems
Loose Wet
Monitor the quality of the overnight crust refreeze, daytime temperatures, and solar inputs. The likelihood of loose wet avalanches will increase as temperatures rise and even short periods of solar inputs can result in increased avalanche activity.
Aspects: East, South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Persistent Slabs
In thin snowpack areas an 80 cm thick midpack slab sits over a weak, facetted base. On most slopes, crusts and the midpack cap this weak base, adding strength as long as they remain frozen. As daytime heating progresses and the surface crust breakdown, triggering this problem becomes easier.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Unlikely
Expected Size: 2 - 3