Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Mar 12th, 2023–Mar 13th, 2023

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
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.

Regions

Crowsnest North, Crowsnest South.

New snow, warm temperatures and strong winds will create dangerous avalanche conditions on Monday.

Continually assess the bond of new snow to old surfaces and give weakening cornices a wide berth.

Confidence

Moderate

Avalanche Summary

On Friday, the South Rockies Field Team was out in the Crowsness Pass. They observed strong ENE winds and building small but reactive pockets of wind slabs directly lee of ridges, trees, and high points. Check out the full report here.

On Saturday, small pockets of reverse loaded wind slabs were reported to be reactive to skier traffic at alpine and treeline.

Snowpack Summary

Accumulating flurries on Monday will cover a variety of surfaces including small pockets of wind slab on exposed south and west slopes, hard wind-affected surfaces in open areas, a sun crust on steep solar aspects, and facetted snow in sheltered areas.

A melt-freeze crust with facets above can be found 50 to 120 cm deep. It has not produced any recent avalanche activity in the region, however, rising freezing levels and additional snow may test this layer through the next few days.

The mid to lower snowpack is considered well-bonded at this point. Currently, we are not seeing the same basal weak layers and reactivity that many of the neighboring regions are experiencing this season.

Weather Summary

Sunday Night

Partly cloudy with isolated flurries, trace accumulation. Alpine temperatures reach a low of -6 °C. Ridge wind 40 km/h from the southwest. Freezing level at valley bottom.

Monday

Cloudy with mixed precipitation, 4-6 cm of new snow accumulation at upper elevations. Alpine temperatures reach a high of 0 °C. Ridge wind southwest 40 km/h gusting to 60 km/h. Freezing levels rise to 1900 meters.

Overnight, flurries intensify bringing 10-15 cm of snow to higher elevations.

Tuesday

A mix of sun and cloud with isolated flurries, trace accumulation. Alpine temperatures reach a high of -3 °C. Ridge wind southwest eases from 60 to 25 km/h. Freezing levels are around 1300 meters.

Wednesday

A mix of sun and cloud. Alpine temperatures reach a high of -2 °C. Ridge wind west 10-25 km/h. Freezing levels rise to 1500 meters.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Wind slabs are most reactive during their formation.
  • Minimize overhead exposure; avalanches triggered by warming or cornice fall may be large and destructive.

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.