Avalanche Forecast

Archived

Mar 14th, 2025–Mar 15th, 2025

Alpine

Natural and human triggered avalanches likely.

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 unlikely, human triggered possible.

Alpine

Below Threshold.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Regions

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

Avalanche danger remains high with a sensitive and persistent problem and a snowpack that has doubled in the last week.

Make conservative terrain choices and avoid large avalanche paths and overhead hazards.

Confidence

High

Avalanche Summary

On Friday an avalanche cycle produced numerous avalanches up to size 3 in alpine terrain, running into treeline. These avalanches showed wide propogation, connecting through multiple terrain features.

Snowpack Summary

A further 20-30cm cm of new snow fell on Thursday brining new snowfall amounts to around 70-80cm. Below this fresh snow, the snowpack is complex, with multiple crusts and facet layers creating persistent weak layers. The bottom of the snowpack consists primarily of weak facets and depth hoar.

Weather Summary

Saturday

Cloudy with scattered flurries.

Accumulation: 5 cm.

Alpine temperature: High -7 °C.

Ridge wind south: 10-25 km/h.

Freezing level at valley bottom.

Sunday

Cloudy with sunny periods and isolated flurries.

Precipitation: Trace.

Alpine temperature: Low -12 °C, High -7 °C.

Mostly light ridge wind occasionally gusting to 40 km/h.

Freezing level at valley bottom.

Monday

Cloudy with sunny periods and isolated flurries.

Precipitation: Trace.

Alpine temperature: Low -12 °C, High -9 °C.

Ridge wind west: 20-30 km/h.

Freezing level at VB

Terrain and Travel Advice

Use conservative route selection. Choose simple, low angle terrain with no overhead hazard.
Avoid exposure to overhead avalanche terrain; avalanches may run surprisingly far.
Recent wind has varied in direction, so watch for wind slabs on all aspects.

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.

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.