Avalanche Forecast

Archived

Feb 14th, 2023–Feb 15th, 2023

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

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

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

Do not trust the snowpack. Your favourite stash has been refreshed with the new snow but the possibility of YOU👈! (Yes, little ol'You!) triggering a large avalanche remains possible. Stick to low-angle, low-consequence terrain.

Confidence

Moderate

Avalanche Summary

No new field observations, or road patrol Tuesday.

Avalanche control with explosives last week resulted in numerous large avalanches both wind slab and deep persistent slab running to the bottom of the avalanche paths.

Don't forget to post avalanche observations to the MIN.

Snowpack Summary

Previous HST settled into 10-15cm soft slab; stiffing to wind slab in exposed areas at treeline and above. Generally the mid and bottom of the snowpack are weak facets with depth hoar at the base. The height of snow is variable from 50 to 150cm.

Weather Summary

Expecting very little change overnight. Cooling trend for the next few days, mostly seasonal temps between -10 and -15. Freezing level will remain at valley bottom in the Icefields area.

Detailed weather forecasts from Avalanche Canada: https://avalanche.ca/weather/forecast

Terrain and Travel Advice

Expect slab conditions to change drastically as you move into wind exposed terrain.
Keep in mind that human triggering potential persists as natural avalanching tapers off.

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.

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.