Avalanche Forecast
Regions: Dogtooth, East Purcell, Purcells, West Purcell.
10 to 20 cm of recent snow and southwest wind have formed wind slabs reactive to human triggers in specific locations below ridgecrests.
Confidence
Moderate
Avalanche Summary
On Thursday, several natural and rider triggered wind slab avalanches up to size 1.5 were reported on mostly northerly aspects at treeline and above.
A few naturally triggered wet loose avalanches up to size 2.5 were reported on steep, sunny slopes in the alpine.
Snowpack Summary
10 to 20 cm of recent snow overlies a crust on all but north facing aspects at treeline and above where a weak layer of surface hoar may be present.
A widespread crust with facets above is buried 40 to 110 cm deep. Steep or convex terrain features with a shallow or thin to thick snowpack at treeline and above are the most likely places to trigger this layer.
Weak facets at the base of the snowpack remain a concern in steep, rocky alpine terrain with a shallow or thin to thick snowpack.
Weather Summary
Friday Night
Mostly cloudy with isolated flurries, 0 to 5 cm snow. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -8° C. Freezing level valley bottom.
Saturday
Sunny. 10 to 20 km/h west ridgetop wind. Treeline temperature -3° C. Freezing level 1700 m.
Sunday
Mostly sunny. 10 to 20 km/h north ridgetop wind. Treeline temperature -2° C. Freezing level 1800 m.
Monday
Sunny. 10 to 20 km/h northwest ridgetop wind. Treeline temperature 3° C. Freezing level 2500 m.
Check out the Mountain Weather Forecast for additional weather information.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Cornice failure may trigger large avalanches.
Avalanche Problems
Wind Slabs
10 to 20 cm of recent snow and southwest wind have formed wind slabs reactive to human triggers in specific locations below ridgecrests.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Persistent Slabs
A crust with weak facets above is down 40 to 110 cm. Steep or convex terrain features with a shallow or thin to thick snowpack at treeline and above are the most likely places to trigger this layer.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3
Loose Wet
Expect the sunshine to trigger wet loose avalanches on sunny aspects at all elevations.
Aspects: North East, East, South East, South, South West, West, North West.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 1.5