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

Nov 9th, 2019–Nov 10th, 2019

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

Regions

Banff Yoho Kootenay.

Watch for fresh wind slabs in steep terrain Sunday, and how any new snow is sticking to the newly formed rain crust which exists up to 2500m. There is still potential to trigger a deeper slab on the Oct. crust near the base of the snowpack.

Weather Forecast

Temperatures will cool off for Sunday with valley bottoms down to -10C and alpine temperatures reaching -15C. Winds will be moderate to strong in the alpine and variable starting as East in the AM switching to W/NW in the afternoon. Forecasts are currently calling for 5-15cm ending tomorrow by midday. Another pulse of weather will arrive Tuesday.

Snowpack Summary

Rain to 2500m on Friday and cooler temperatures Saturday have started to form a crust today which is 1-5cm thick. The thin October crust and facets in the lower snowpack have been found up to about 2300m. Some wind slabs in the high alpine have still been observed. Treeline snow depths range from 50-70 cm deep (up to 110 cm in lee areas).

Avalanche Summary

Some smaller wind slabs in the alpine have been observed in the last 24 hours outside of the sunshine ski area boundary. Also one planned ski cut in bounds at treeline which likely stepped down to the October rain crust. No other observations reported today.

Confidence

Due to the number and quality of field observations

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.