Avalanche Forecast
Issued: Dec 11th, 2019 8:02AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
chris gooliaff,
Parks Canada
Be aware of where other groups are traveling. Some unconventional up-tracks in the Rogers Pass area climb directly up the normal ski-line.
Reduce your exposure time by taking a safe route up.
Summary
Weather Forecast
Mainly cloudy today with flurries picking up in the afternoon, light SW winds at ridgetop, and alpine highs near -8*C. Wed night and Thursday will see a continuation of the flurries, amounting to ~10-15cm, with gusty, moderate SW winds and alpine highs around -5*C. Scattered flurries on Friday bring 5cm, light SW winds, and -7*C in the alpine.
Snowpack Summary
Moderate S-SW winds have created wind slabs in lee alpine features. Clear skies and cool temps have promoted faceting in the new snow, as well as surface hoar growth. The Dec 5 surface hoar is 30-40cm down and is stubborn in tests. The November 23rd surface hoar/crust/facet layer is buried 80-100+cm and is becoming stubborn in stability tests.
Avalanche Summary
Several natural avalanches, sz 2-2.5, were observed from both N and S aspects in steep, alpine start zones above the highway yesterday. No avalanche activity was noted from the backcountry yesterday. On Monday, human triggered avalanches to sz 2 were reported from steep, S-facing alpine start zones (Tupper and Ursus Major), failing on a crust.
Confidence
Problems
Persistent Slabs
The November 23rd layer is down 80-100+cm and consists of surface hoar at treeline and below, and a crust on steep solar aspects into the alpine.
- If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Recent periods of moderate wind have potentially built wind slabs in immediate lees. Keep an eye out for these as you transition into exposed alpine terrain.
- Use caution in lee and cross-loaded areas. Recent wind loading has created new wind slabs.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 12th, 2019 8:00AM
