Avalanche Forecast
Issued: Jan 9th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
ldreier,
Avalanche Canada
The recent storm snow is gaining strength. However, it might still be possible to trigger deeper weak layers in the snowpack.
Summary
Confidence
Weather Forecast
THURSDAY NIGHT: Cloudy with clear periods, light to moderate northwest wind, alpine temperature -16 C, freezing level below valley bottom.
FRIDAY: Cloudy with snowfall, accumulation up to 10 cm, moderate southwest wind, alpine temperature -12 C, freezing level below valley bottom.
SATURDAY: Cloudy with flurries, accumulation up to 15 cm, light to moderate southwest wind, alpine temperature -8 C, freezing level at 400 m.
SUNDAY: Cloudy with snowfall, snow accumulation 5 to 10 cm, moderate to strong southwest wind, alpine temperature -8 C, freezing level below valley bottom.
Avalanche Summary
On Wednesday, a few natural and one skier triggered slab avalanche of size 3 were reported. These avalanches released on a weak layer consisting of feathery surface hoar which was buried at the end of December and is now between 50 and 120 cm deep. Numerous explosive triggered storm slab avalanches of up to size 3 were reported.
On Tuesday, a widespread natural avalanche cycle occurred in the region with large storm slab avalanches to size 3.5. Numerous explosive and skier triggered storm slab avalanches up to size 2.5 were reported.
Snowpack Summary
Up to 10 cm snow accumulation are expected during the day on Friday. The previous storm delivered around 40 to 70 cm of snow which fell with strong southwest wind. The formed slabs may still be sensitive, particularly in exposed lee terrain features.
Deeper in the snowpack, a few layers of weak and feathery surface hoar may still be found around 50 to 150 cm deep. It is unclear whether they are still problematic and if so, how long they will be so for. The base of snowpack is also weak in parts of the region, where it consists of sugary faceted snow around a melt-freeze crust. Until these weak layers can be ruled out, best to travel conservatively.
Terrain and Travel
- Conditions may have improved, but be mindful that deep instabilities are still present.
- If triggered, storm slabs in-motion may step down to deeper layers and result in very large avalanches.
- Don't let the desire for deep powder pull you into high consequence terrain.
Problems
Storm Slabs
Up to 10 cm of snow are forecast during the day of Friday with moderate southwest wind. The previous storm delivered around 40 to 70 cm of snow in the region, forming a widespread natural avalanche cycle on Tuesday. Storm slabs may remain sensitive to human traffic, especially in lee terrain features in the alpine and around treeline, where the snow was transported with strong southwest wind.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Several persistent weak layers are buried in the snowpack. It might still be possible for humans to trigger them, or for storm or wind slab avalanches to step down to them and form very large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 10th, 2020 5:00PM
