Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Login
Archived

Avalanche Forecast

Dec 17th, 2017–Dec 18th, 2017
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: Purcells.

Snow amounts will gradually accumulate over a variety of potential weak layers in the coming days.

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Tuesday

Weather Forecast

MONDAY: Snow Sunday night into Monday accumulations 5-10cm then cloudy with scattered flurries / Light to moderate west / Alpine temperature -5 TUESDAY: Periods of snow accumulations 10-15cm / Light to moderate west wind / Alpine temperature -10 WEDNESDAY: Cloudy with isolated flurries / Light west wind / Alpine temperature -11

Avalanche Summary

Recent reports in the north of the region indicate numerous size 1 wind slab avalanches in the lee of terrain features in the alpine. Please submit any observations you may have to the Mountain Information Network (MIN).

Snowpack Summary

The 10-15cm of new snow accumulating Friday through Sunday evening now sits on a wide variety of old surfaces including large surface hoar (weak, feather-like crystals), hard crusts formed by sun or wind, and sugary facets. As the snow load builds and slab properties develop, it will be important to monitor how the new snow is bonding to the old surfaces. Most concerning would be areas that have surface hoar sitting on top of a hard crust. A crust which was formed by rain in late November is a major feature in the snowpack and is down approximately 40-60cm at tree line elevations. Snowpack tests suggest the snow above is currently bonding well to it.Snowpack depth decreases rapidly below tree line. Look out for early season hazards such as rocks, stumps, and open creeks.

Avalanche Problems

Wind Slabs

New snow combined with moderate westerly winds will have formed wind slabs in alpine lees that may be reactive to human triggers.
Be cautious as you transition into wind affected terrain.Travel on ridges and/or ribs to avoid wind loaded slopes below

Aspects: North, North East, East, South East, South.

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2