Avalanche Forecast

Archived

Dec 24th, 2023–Dec 26th, 2023

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

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

It'll be smooth, but cold sailing for Santa and his hooved helpers tonight. His beacon has been checked and he's on his way. Tomorrow looks like a beautiful day to get out and enjoy Christmas. Merry Christmas and happy Holidays!

Confidence

Moderate

Avalanche Summary

Nothing was noted today.

Snowpack Summary

Given the quick cooling, alpine wind slabs have stiffened up a bit which will make them slightly more sensitive for the day or so. Where untouched by wind, the recent storm snow has had enough time to improve its bond and stick to the underlying surface. There is talk of winds arriving tomorrow which could build new wind slabs. If that's the case, look for plumes coming off ridges and summits as a hint for where they'll be. And what about the crust you ask? In the short term it will continue to help us by bridging the good and the bad layers. But as time goes on, and the cold sinks into the snow, expect unstable facets to develop above the crust. This will happen in shady areas first. We probably have some time on our hands before this happens, but it should be on every climber and skier's radar. No snowpack summary is complete without a quick blurb about the deeper, basal problems. Depth hoar (extremely loose snow), is out there lurking at the bottom. Thick to thin transitional areas are the likely places for us to disturb it and cause a big avalanche.

Weather Summary

Whoever ordered the blue skies for their Christmas gift must have an in with Santa. No coal for that kid. Like today, tomorrow will be clear and blue for the entire day. The morning will be chilly at -18 or so, but expect that to perk up to -9 by mid afternoon. The only blemish on the day will be a chilly alpine wind from the SW. This pattern will take up to mid morning on the 26th.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Wind slabs are most reactive during their formation.
Approach lee and cross-loaded slopes with caution.

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.