Avalanche Forecast
Issued: Jan 16th, 2021 8:09AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
Kate Ryan,
The recent storm snow has gained strength quickly, however uncertainty remains with the Jan 10 SH interface.
Take the time to identify weak layers as you travel today.
Summary
Weather Forecast
High pressure builds today, but will be pushed out by a cold front tonight.
Today: Cloudy with isolated flurries and sunny periods. Freezing level 1000m. Winds SW 15 to 25 km/h.
Tonight: Scattered flurries, 5cm. Freezing level 700m. Winds SW-25 to 35 km/h.
Sunday: Scattered flurries, 5cm. Freezing level 1200m. Winds W-25 km/h gusting to 55 km/h.
Snowpack Summary
The recent storm dropped 40cm snow burying a thin crust from sun and/or rime in exposed terrain. Jan 10 surface hoar resides under the storm snow in sheltered terrain at treeline and below. The spotty Dec 26 surface hoar is down 70-90cm. The Dec 7th surface hoar/crust/facet layer is down 1.5m. Crusts with facets persist at the base of the snowpack.
Avalanche Summary
No new avalanches observed yesterday. Field team members remotely triggered a size 1 slab on Jan 10 surface hoar at 1900m in the west end of the park. The Lone Pine path glide crack on Mt Tupper released to ground size 3 on Thursday. Wednesday's natural avalanche cycle and avalanche control produced numerous size 3 slides and even a couple size 4.
Confidence
Problems
Persistent Slabs
This layer is capped by a thin crust in many locations making it stubborn to initiate, however it has proven that it can still be triggered in sheltered locations. Avalanches caused by this layer may fracture above you!
- Watch for whumpfing, hollow sounds, and shooting cracks.
- Dig down to find and test weak layers before committing to a line.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Wind Slabs
The strong to extreme S-W winds that accompanied the recent storm has left wind slabs on lee features. Many of these slabs have lost their energy, however some are still able to be triggered in isolated pockets.
- Watch for whumpfing, hollow sounds, and shooting cracks.
- Use caution in lee areas. Recent wind loading has created wind slabs.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 17th, 2021 8:00AM
