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

Apr 8th, 2021–Apr 9th, 2021

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

Regions

Little Yoho.

The avalanche hazard will increase over the day as forecasted winds intensify, watch for fresh wind slab.

Uncertainty exists around the persistent layers in the snowpack, as some deep releases have occurred recently and lowered our confidence.

Weather Forecast

A mix of sun and cloud for the majority of Friday as 5-10cm of snow is forecasted for late Friday afternoon into Saturday morning. Winds are expected to be 30-75km/hr from the South West. Freezing levels will reach 1400m. Clearing trend for early next week.

Snowpack Summary

10-20cm of snow in the past 24hrs now buries a crust up to 1800m, higher on steep solar aspects. New wind slab growth in the alpine down into tree line. Several persistent layers exist in the mid to lower snowpack and have been responsible for several large avalanches. These layers will remain a concern for some time due to their uncertainty.

Avalanche Summary

A loose dry avalanche cycle occurred during the intense flurries on Thursday. Several cornice failures and small slab releases digging down and triggering deep releases up to size 3.5 over the last 4 days (Des Poilus, Vulture Pk, Lake Louise area, etc.). A nearly, full burial occurred on Wednesday in alpine terrain around Lake Agnes, no injuries.

Confidence

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.

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.