Avalanche Forecast
Issued: Feb 19th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
TRettie,
Avalanche Canada
Carefully assess the wind effect as you gain elevation. Use extra caution near ridge crests and steep roll overs.
Summary
Confidence
Weather Forecast
Saturday night: low of -5 at 1500m. flurries bringing up to 5cm of snow and winds shifting to light northwest.
Sunday: a mix of sun and clouds with no new snow expected. Light northerly winds and a high of -3 at 1500m.
Monday: sunny with a high of -8 at 1500m. Light north winds.
Tuesday: sunny with a high of -12 at 1500m. Moderate north wind.
Avalanche Summary
Early reports Saturday afternoon indicated thin wind slabs were reactive to ski cutting just below ridge crests..
On Thursday a natural icefall triggered a size 2.5 avalanche on the slope below. This avalanche was on a northeast aspect at 2100m.
On Wednesday one size one natural cornice fall was observed on a east aspect at 2200m. It was in extreme terrain and did not pull a slab on the slope below.
Snowpack Summary
New snow and southwest winds on Saturday will likely have formed wind slabs on north and east aspects.
The mid February crust is down 10 to 30cm . This melt-freeze crust is reported to exist on all aspects and elevations except for some of the highest elevation polar aspects. Facets have been observed above the crust on polar aspects.
The late-January crust/facet/surface hoar interface is buried down 40 to 100cm. This layer was most reactive between 1700 m and 2000 m. While this layer now appears to be dormant in many parts of the region it may be possible to trigger it with a large load or in shallow snow pack areas at upper treeline or lower alpine features on polar aspects.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Closely monitor how the new snow is bonding to the crust.
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
Problems
Wind Slabs
Recent new snow and southwest wind will likely have formed wind slabs in exposed treeline and alpine terrain. Strong winds mean that wind slab may be found further down slope then expected.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
The late-January weak layer is down 40 to 100 cm and was most reactive between 1700 and 2000 m. It is now likely dormant in many areas. It is likely only possible to trigger on polar aspects at upper treeline or lower alpine where the mid February crust is thinner and not bridging.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 20th, 2022 4:00PM
