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

Avalanche Forecast

Nov 25th, 2017–Nov 26th, 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
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
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

Regions: Kootenay Boundary.

Rain may weaken the upper snowpack Sunday afternoon. Due to limited data it is CRITICAL to supplement this information with your own observations. Please post your observations to the MIN.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

The next weather system will initially bring rain on Sunday afternoon, changing to snow and lingering light flurries early next week. SUNDAY: 10-20 mm rain giving way to 5-10cm snow late Sunday. Moderate to strong southwesterly ridgetop winds. Freezing level around 2500 m lowering to surface overnight. MONDAY: Cloudy with isolated flurries. Light to moderate westerly ridgetop winds. Freezing level around 1000 m.TUESDAY: Flurries (10-15cm possible). Light-moderate southerly ridgetop winds. Freezing level around 1000 m.

Avalanche Summary

No new avalanches reported; however, we currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

A new crust formed on Thursday as temperatures cooled and the rain-soaked snow surface froze and then was covered by 5-10cm of snow at treeline and above. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 100+cm in the alpine, 50-100cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. Recent heavy rain to the mountaintops has rapidly shrunk the snowpack and has transitioned much of the snowpack from dry to moist snow. The major feature in the snowpack is a crust which was formed at the end of October can be found approximately 30cm above the ground in some locations. That said, the new surface crust will temporarily reduce the likelihood of triggering on this layer. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.

Avalanche Problems

Loose Wet

The precipitation on Sunday will start as rain, which could saturate the upper snowpack. Even a small avalanche can push you into terrain traps.
Watch out for wet sloughs in steep terrain, particularly where the debris flows into terrain traps.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

Recent rain to mountaintops combined with overnight cooling Thursday night has reduced the likelihood of triggering this layer. Areas in which the snowpack above this layer remained dry should be treated with increased caution.
Use increased caution in areas which did not form a surface crust.Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3