Avalanche Forecast
Regions: Little Yoho.
20 cm of soft surface snow made for excellent ski quality on Mt Field today. We continue to be wary of the Dec 18 surface hoar, as we dig in various locations to try and track its distribution and strength.
Weather Forecast
The westerly flow continues with no snow in the forecast until early Thursday morning. Treeline temperatures on Wednesday will range from -5 to -10 with alpine winds increasing to 50-60 km/hr by the afternoon. A total of 10 cm of snow is expected by Friday.
Snowpack Summary
The snowpack in the Emerald Lake and Mt Field area is about 130cm deep, with the main weakness being the Dec 18 surface hoar down 50 cm. This layer continues to produce moderate results, but the layer is not found in all areas. We suspect some bonding is occurring with this layer, but remain careful. Windslabs exist in open, alpine areas.
Avalanche Summary
No natural avalanches observed, but human and explosive triggered avalanches persist. Yesterday someone in the Sunshine Village backcountry triggered a windslab that took them for a 50m ride. Avalanche control on Mt Dennis in Field today produced no slabs, but loose snow avalanches ran 1000m over Pilsner Pillar.
Confidence
Avalanche Problems
Wind Slabs
Windslabs in leeward areas can be found up to 25 cm deep. Watch for convex rolls or other areas of wind loading where the snow can be under tension.
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2
Persistent Slabs
The Dec 18 SH continues to be found 50 cm down, but the layer becoming harder to find, and is slowly bonding to the overlying snow. Regardless, this layer continues to command respect.
- Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.
- Choose conservative lines and watch for clues of instability.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 2 - 3