Few observations and little information means lots of uncertainty in the forecast. Be cautious in lee areas where wind slabs have formed. If triggered these slabs may have the potential to step-down to a deeper layer.
Confidence
Low - Due to the number and quality of field observations
Weather Forecast
Flurries with up to 10-15 cm of snow and strong west winds are forecasted for Sunday night.Monday: Mix of sun and cloud. Moderate to strong west wind. Alpine temperature -8. Freezing level 1100m.Tuesday: Flurries. Accumulation 5-10 cm. Moderate to strong west wind. Alpine temperature -5. Freezing level 1200m.Wednesday: Mix of sun and cloud. Moderate to strong west wind. Alpine temperature -10. Freezing level 1100m.
Avalanche Summary
There is very little information or observes in the region at this time. To the north, Kananaskis Country reported natural, persistent slab activity to Size 2.5 initiating on a east aspect at 2700m in the alpine and running to treeline, damaging trees on Saturday. While natural avalanche activity is likely to taper off with a return to cooler temperatures and lowering freezing levels, the possibility of triggering a deeper layer in the snowpack still exists.
Snowpack Summary
Last week saw rain drench the snowpack from valley bottom to mountain top, followed by 10-15 cm of snow at higher elevations. Warm temperatures and high freezing levels again on Sunday are suspected to have brought light rain up to 2400m and light snow above. Snowpack depths across the region are suspected to vary from 40-60 cm at 1800m elevation to 80-100 cm near 2300m. Several crusts are expected to exist within the snowpack including the most recent rain crust which is now buried by 10-15 cm of moist snow. Below this crust lies the Halloween crust as well as the early October rain crust at the base of the snowpack, and the snowpack is believed to be moist to ground.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.