Avalanche Forecast

Archived

Mar 10th, 2023–Mar 11th, 2023

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 possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

Solar warming combined with a significant temperature swing of up to 20 °C throughout the day is stressing the already weak snowpack.Ice climbers should avoid sun-exposed climbs during peak warming and be aware of potential overhead hazard.

Shaded, North facing slopes will have better skiing at treeline and below.

Confidence

Moderate

Avalanche Summary

Avalanche control using explosives on Hwy 93N resulted in few wind slabs and numerous loose dry avalanches up to size 2 on Wednesday, March 8.

No new natural avalanche activity has observed on Maligne Road or Icefields Parkway.

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

Snowpack Summary

A sun crust has formed on solar slopes at tree line and below. Wind sheltered areas and sun-protected slopes have 20 to 40cm of low density facetted snow. There is extensive wind effect at tree line and above from previous SW winds.

The mid and lower snowpack is generally weak and faceted with depth hoar lingering at the base. Snowpack depth varies from 60 to 160cm.

Weather Summary

Saturday

Cloudy with sunny periods and isolated flurries.

Precipitation: Trace.

Alpine temperature: High -9 °C.

Ridge wind south: 10-20 km/h.

Freezing level at valley bottom.

Sunday

Mainly cloudy with scattered flurries.

Accumulation: 5 cm.

Alpine temperature: Low -13 °C, High -8 °C.

Ridge wind southwest: 15-35 km/h.

Monday

Periods of snow.

Accumulation: 16 cm.

Alpine temperature: Low -12 °C, High -5 °C.

Ridge wind southwest: 15 km/h gusting to 40 km/h.

Freezing level rising to 1600 metres.

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

Terrain and Travel Advice

If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

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.