Avalanche Forecast
Regions: Dogtooth, East Purcell, Purcells, West Purcell.
If a thick surface crust is present, avalanche activity is unlikely.Buried weak layers continue to produce large avalanches that may run to valley bottom.
Confidence
Low
Avalanche Summary
On Wednesday, several small storm slabs (size 1.5) were triggered with explosives in the alpine on north to northwest aspects.
On Tuesday, there were several natural and rider-controlled wind slabs, mostly small, but up to size 2.
A recent large persistent slab (size 2.5) seen near Panorama is suspected to have occurred in the past 4 days. From a northeast aspect in the alpine.
Persistent slab avalanches have been occurring on northerly slopes in the alpine.
Snowpack Summary
Around 10 to 30 cm of snow this week, with the most on the west side of the region, likely melted and is expected to refreeze into a crust. If it is cloudy overnight, the crust may be thin and break down quickly. Northerly slopes in the alpine are unlikely to have a surface crust.
Several weak layers can be found in the mid and lower snowpack. These layers remain a concern where there is no thick crust above them.
The base of the snowpack is generally faceted.
Weather Summary
Thursday Night
Cloudy with 5 to 10 mm/cm of rain/snow. 40 to 60 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 2200 m.
Friday
Mostly cloudy. 20 to 30 km/h west ridgetop wind. Treeline temperature -2 °C. Freezing level 1900 m.
Saturday
Mostly cloudy with 5 to 10 cm of snow. 10 km/h northwest ridgetop wind. Treeline temperature -4 °C.
Sunday
Sunny. 10 km/h west ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
- Be aware of the potential for large avalanches due to buried weak layers.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Avalanche Problems
Persistent Slabs
Several persistent weak layers exist in the upper meter of the snowpack. Persistent slab avalanches are possible in areas without a thick surface crust.
Aspects: North, North East, North West.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2.5 - 3.5
Storm Slabs
Storm slabs may be triggered by riders on high elevation slopes with no surface crust.
Aspects: North, North East, North West.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2
Loose Wet
Wet loose avalanches may occur in areas that don't have a surface crust.
Aspects: East, South East, South, South West, West.
Elevations: Treeline, Below Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2