Avalanche Forecast

Archived

Mar 3rd, 2025–Mar 6th, 2025

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.

The widespread natural avalanche cycle that occurred this weekend should be slowing down with cooler temperatures but the potential for human triggered avalanches may still be likely.

We are dealing with a complex snowpack that varies greatly from slope to slope.

Confidence

Moderate

Avalanche Summary

Warm weather on the weekend produced natural persistent slab avalanche activity up to size 2.5, along with numerous wet loose avalanches to size 2.

On Monday there were more wet loose avalanches observed up to size 1.5 on solar aspects.

Neighboring regions reported numerous natural size 2-3 avalanches over the weekend as well as explosive results up to size 3.5.

Snowpack Summary

The Icefields received up to 10 cm of new snow on Sunday night that now sits on a sun crust on solar aspects to mountaintop. Recent winds have scoured some areas and deposited snow in others. The upper 50 cm of the snowpack has a variety of persistent weak layers including facets, surface hoar, crusts and old wind slabs. Lots of variability exists in the upper snowpack depending on the slope. The bottom of the snowpack is comprised of weak facets and depth hoar.

Weather Summary

Tuesday

Mainly cloudy with isolated flurries.

Precipitation: Trace.

Alpine temperature: High -7 °C.

Ridge wind southwest: 10-20 km/h.

Wednesday

Flurries.

Accumulation: 6 cm.

Alpine temperature: Low -7 °C, High -4 °C.

Ridge wind west: 10-20 km/h.

Thursday

A mix of sun and cloud.

Precipitation: Nil.

Alpine temperature: Low -8 °C, High -4 °C.

Light ridge wind.

Terrain and Travel Advice

Be mindful that deep instabilities are still present in the snowpack.
Keep in mind that human triggering may persist as natural avalanches taper off.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

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.