Avalanche Forecast
Issued: Jan 8th, 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
Storm slabs may remain sensitive to human triggering and have the potential to step down to deeper weak layers. It is uncertain how fast the snowpack will recover and gain strength. Assess the snowpack and travel conservatively to safely manage the avalanche problems.
Summary
Confidence
Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.
Weather Forecast
WEDNESDAY NIGHT: Clear sky with some clouds and isolated flurries, light northwest wind, alpine temperature -14 C, freezing level below valley bottom.
THURSDAY: Mix of sun and cloud, light northwest wind, alpine temperature -17 C, freezing level below valley bottom.
FRIDAY: Cloudy with snowfall, accumulation 5 cm, moderate southwest wind, alpine temperature -12 C, freezing level below valley bottom.
SATURDAY: Cloudy with flurries, light southwest wind, alpine temperature -8 C, freezing level at 400 m.
Avalanche Summary
On Wednesday, a few natural storm slab avalanches of size 2 were observed. Several explosive triggered storm slab avalanches of up to size 2 were reported.
A widespread natural avalanche cycle occurred in the region on Tuesday with large storm slab avalanches to size 2.5. Numerous explosive and skier triggered storm slab avalanches up to size 2.5 were reported.
Snowpack Summary
Around 40 to 70 cm of snow fell in the region during the most recent storm, which formed touchy storm slabs. The slabs may be particularly touchy in exposed lee terrain features, as the snow fell with strong southwest wind.
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
- Don't let the desire for deep powder pull you into high consequence terrain.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- If triggered, storm slabs in-motion may step down to deeper layers and result in very large avalanches.
Problems
Storm Slabs
Around 40 to 70 cm of snow accumulated in the region, forming a widespread natural avalanche cycle. Storm slabs may remain sensitive to human traffic on Thursday. Make assessments as you travel and do so conservatively until there is evidence that the recent snow is bonding.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Several persistent weak layers are buried in the snowpack. It still may be possible for humans to trigger them, or for storm slab avalanches to step down to them and form very large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 9th, 2020 5:00PM
