Avalanche Forecast
Regions: Bow Valley, Highwood Pass, Kananaskis, North 40, Spray - KLakes.
Some snow is forecast for the weekend but currently the high pressure ridge is holding strong. Avoid being under or on solar exposed slopes as they become affected by warming temps and solar input. Thin weak spots should still be avoided as they may trigger the basal weaknesses.
Confidence
Moderate
Avalanche Summary
No new avalanches observed or reported over the past 24hrs.
Snowpack Summary
Sun crusts on solar aspects at all elevations where the terrain is steeper than about 20 degrees. The strong late March sun is melting these surface crusts and destabilizing the slopes. There are previously formed wind slabs in alpine areas, so keep an eye out for these in lee and cross-loaded features. The midpack remains highly variable with areas of more than 100cm of total snowpack being supportive, but in shallower areas ski penetration can still be to ground. The good old facets and depth hoar still lurk at the bottom of the snowpack and present an ongoing concern for full-depth avalanches. Expect the avalanche hazard to deteriorate throughout the day with the solar input and rising freezing level. This will be of greatest concern under larger features where the solar radiation could trigger the deep persistent layer.
Weather Summary
No new snow is forecast over the next 24hours but some in later in the week.... Freezing levels will be around 1700m on Thursday with generally light SW winds throughout the day. A mix of sun and clouds will keep the solar radiation at bay but when the sun does come out it packs a punch and can decrease stability quickly on solar aspects.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Cornices become weak with daytime heating or solar exposure.
Avalanche Problems
Deep Persistent Slabs
Avoid exposure to large features as the deep persistent slab can be triggered with solar radiation. The alpine is still variable in total amounts of snow but the basal layers haven't changed. The entire lower half is either facets or depth hoar.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 3.5
Persistent Slabs
On solar aspects this slab most likely is starting to sit on top of buried sun crusts on S-W aspects. On polar aspects the interface is facets and surface hoar.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2