Avalanche Forecast

Archived

Feb 23rd, 2025–Feb 24th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

The Icefields Parkway should be open Monday by noon. Check for updates on https://511.alberta.ca/.Do not be bold as the volume of new snow means things have changed. Be cautious in avalanche terrain while the snowpack is adjusting to the new snow load.

Confidence

Moderate

Avalanche Summary

Explosive control work at Parkers ridge area resulted in several size 2 storm / wind slabs. A size three was observed in the Alpine on Mount Amery. Where the sun poked out, loose wet activity was noted on steep solar aspects at all elevations. Otherwise the visibility was poor and one should assume there was more activity.

Snowpack Summary

Parkers ridge received 20-30cm of snow Saturday night. Winds are whipping it around at alpine ridgetops. The new snow rests on previous temperature crusts, surface hoar, surface facets, or a hard wind buffed surface. The midpack is weak and faceted. The bottom is large depth hoar.

Weather Summary

Monday will bring clouds, flurries, -6 °C, 15 gusting 50 km/h winds. Tuesday will be more sun, flurries, -9 to -4 °C, and light winds. Wednesday will be flurries and 15 gusting 40 km/h winds.

Terrain and Travel Advice

Continue to make conservative terrain choices while the storm snow settles and stabilizes.
Use increased caution at all elevations. Storm snow is forming touchy slabs.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.

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.