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

Feb 12th, 2024–Feb 13th, 2024

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

Regions

Banff Yoho Kootenay, Little Yoho, Banff, East Side 93N, Kootenay, Lake Louise, LLSA, Sunshine, West Side 93N, Field.

Small wind slabs on the immediate lee of alpine ridges and features linger as a concern. Some weaknesses persist in the mid and lower snowpack, and while reactivity of the lower layers has been limited, avalanches are still possible. Keep this in mind if entering steep committing terrain.

Confidence

No Rating

Avalanche Summary

No new natural avalanches were reported today. A spike in wind on Saturday resulted in numerous reports of wind slab avalanches (size 1 to 1.5) failing on the Feb. 3 crust. Also, there were a couple of deeper and larger releases, mainly on the mid-pack facets, but also a deeper one to ground in steep terrain on Fairview in the last 48 hours.

Snowpack Summary

Wind slabs have formed in lee areas of the alpine with west winds over the weekend. At treeline, 10-25 cm of recent storm snow sits over the Feb 3 crust. The Feb 3 crust is present on all aspects except north above 2500 m and ranges from 1-15 cm thick, with the thickest found in Yoho. Mid-pack persistent weak layers from Jan and Dec are down roughly 30 and 50 cm respectively. Facets and depth hoar make up the basal layers of the snowpack in most locations.

Weather Summary

Monday night: NW wind 20-30 km/hr no snow and increasing clouds through the night.

Tuesday: Cloudy skies in the morning with 2-4 cm along the Eastern part of the region. As a high-pressure system builds, skies will clear through the remainder of the day, winds will become light, and temperatures will drop with overnight lows dipping to -18C on Wednesday night.

For more mountain weather, click HERE.

Terrain and Travel Advice

  • Wind slabs may be poorly bonded to the underlying crust.
  • Watch your sluff: it may run faster and further than you expect.
  • Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

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.