Avalanche Forecast

Archived

Jan 6th, 2024–Jan 7th, 2024

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.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Change is in the air. As the first cold snap approaches, we're expecting unsettled conditions that will bring some snow. Amounts will be variable and difficult to forecast so keep a close eye on locally changing weather patterns.

Confidence

Moderate

Avalanche Summary

Some isolated loose dry avalanches and sluffs from very steep and prominent cliffs. Poor visibility prevented a good look around.

Snowpack Summary

Another 4-8cm fell last night, giving us up to 15cm near the divide and along the main ranges of the Spray valley but tapering with elevation. Winds have been in the light to moderate range at ridgetop with frequent gusts from a variety of directions. Windslabs have begun to form in all lee areas. By tomorrow, they will be sitting on a variety of old surfaces with lots of variability given the amount of exposed gravel and old hard slab. The buried crust will likely tolerate and support this new load. Reactive windslabs and loose dry avalanches will be the main concern.

Weather Summary

The forecast is calling for 6cm tonight, but that amount could be higher as the flurries get hung up on the divide. Even if its only 6, that will put us at about the 15cm mark for the past 2 days and possibly more. Tomorrow will see continued flurries with temperatures dropping during the day. Minus 16 will be the rough target for temperatures. Winds will be shifting to an upslope (easterly) flow tonight and stay that way until noon tomorrow when they'll shift back to westerly. As the weather fronts duke it out there could be gusts from variable wind directions. Snow amounts, wind direction/intensity will likely vary from the forecasts. Pay attention to rapidly changing conditions.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Dial back your terrain choices if you are seeing more than 20 cm of new snow.
Be carefull around freshly wind loaded features.

Problems

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.

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.