Avalanche Forecast
Issued: Feb 11th, 2023 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
Avoid wind loaded slopes near ridge crests where triggering avalanches is more likely.
Summary
Confidence
Moderate
Avalanche Summary
On Friday skiers were able to intentionally trigger small wind slabs. Check out the MIN for more details.
On Wednesday, skiers triggered a large, size 2 avalanche near Ningunsaw. The Deep Persistent avalanche was triggered on an east aspect near ridgetop in a thin, rocky start zone and failed on basal facets.
Reports Tuesday documented a very large (size 3.5) natural deep persistent slab avalanche observed in the Babines on a northwest aspect around 1700 m and failing on basal facets 150 cm deep. This speaks to the importance of conservative terrain selection through this period of active weather. Several less surprising small to large (size 1-2.5) naturals were also observed in steep leeward terrain in the same area.
Observations from Monday in the snowier southwestern part of the region show our recent storm snow reacting to ski cutting, which produced numerous small (up to size 1.5) storm slabs on steep slopes at treeline and below with crowns up to 40 cm. Isolated natural releases were also observed in the alpine.
If you are out in the backcountry, please share your observations with the Mountain Information Network!
Snowpack Summary
50 to 80cm of recent storm snow has been redistributed into wind slabs on north and east aspects by ongoing southerly winds. The above mentioned storm snow sits on a crust layer from late January.
The mid and lower snowpack continues to bond and stabilize. A few concerning weak layers can still be found in the top meter of the snowpack including a surface hoar layer from early January and a crust from late December.
Weather Summary
Saturday Night
Cloudy with around 5 cm of new snow expected. Moderate to strong southwest winds and a low of -1 at 1500m.
Sunday
Stormy with 5 to 10cm of new snow expected. Strong southwest winds and a high of -3 at 1500m.
Monday
A mix of sun and cloud with the possibility of light flurries bringing trace amounts of new snow. Moderate westerly winds and temperatures at 1500m falling throughout the day to -9.
Tuesday
Sunny with no new snow expected. Light westerly winds and a high of -10 at 1500m.
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.
- Make observations and assess conditions continually as you travel.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Avoid areas with a thin or variable snowpack.
Problems
Wind Slabs
Ongoing southwest winds and new snow will add to the wind slab problem.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A number of buried weak layers remain possible to trigger. These layers appear to be most problematic in upper treeline and alpine elevations, in shallow, variable, rocky start zones. A sensitive wind or storm slab overlying this problem could serve as the perfect trigger for a destructive step-down avalanche.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 12th, 2023 4:00PM
