Wind Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible - Likely
- Size
- 1–2
Newly formed wind slabs could be reactive to human triggers.
Avalanche forecast
View on mapNorth Rockies
Mar 20 – 21, 2025Avalanche Canada
Archived · expired 2 years ago
Avalanche danger
Sat
Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Highlights
Use caution as you transfer into wind-affected terrain.
Human-triggered avalanches are possible.
Avalanche problems
Confidence
Moderate
Avalanche Summary
Three natural wind slab avalanches were reported on Wednesday. One large (size 2) and two were triggered by cornice failures. One size 2 and one small (size 1) naturally triggered wind slabs were reported on Tuesday.
Snowpack Summary
30 to 60 cm overlies a hard melt-freeze crust and surface hoar crystals in some wind-sheltered treeline terrain.
Variable winds have created windslabs on all aspects near or just below ridge crests in the alpine and treeline elevations.
A weak layer of surface hoar and/or faceted grains buried mid-February is around 50 to 100 cm deep. This layer seems to be gaining strength.
The lower snowpack is well-settled.
Weather Summary
Thursday night
Cloudy with 0 to 5 cm of snow. 20 to 40 km/h south ridgetop wind. Treeline temperature -4 °C.
Friday
Cloudy with 0 to 5 cm of snow. 20 to 40 km/h southwest ridgetop winds. Treeline temperature -5 °C. Freezing level 1300 m.
Saturday
Mix of sun and cloud with 0 to 5 cm of snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1300 m.
Sunday
Cloudy with 5 to 10 cm of snow. 40 to 60 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1600 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Expect slab conditions to change drastically as you move into wind-exposed terrain.
- Recent wind has varied in direction, so watch for wind slabs on all aspects.