Avalanche Forecast

Archived

Nov 27th, 2022–Nov 28th, 2022

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Saturday night's 15cm of new snow overnight was localized at the Parker's ridge area. It is adding to the snow load on a potentially weak buried Surface hoar layer approximately 30cm down. This layer's distribution is still being assessed so important to evaluate snow and terrain carefully, investigate for it's presence, and assume human triggered avalanches are possible. It is November and early season conditions exist everywhere with a lot of spatial variability.

Confidence

Moderate

Avalanche Summary

No field patrol occurred on Sunday and nothing new was reported. On Saturday, several Loose Dry avalanches up to size 1.5, and one size 2 wind slab were observed in the icefields area. Cracking and small slabs were triggered in wind effected areas at tree line yet did not propagate.

Snowpack Summary

25-35cm overlies a Surface hoar-Facet-crust combination layer depending on aspect and elevation. 6mm Surface hoar is found preserved in treeline Hilda ridge sheltered locations. Moderate to strong Southwest winds have created a wind slab in most exposed locations. Height of snow ranges from 60 to 100cm.

Weather Summary

Sunday night will be clear with isolated flurries, trace amount of snow, -24 °C, and light North winds. Monday will bring sun and clouds, no new snow, -20 °C, and light Northeast winds. Tuesday will be similar. Wednesday may have cloud and flurries, 5cm of snow, -29 °C to -14 °C, and light South winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Avoid terrain traps such as gullies and cliffs where the consequence of any avalanche could be serious.

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.