Avalanche forecast

Banff Yoho Kootenay

Dec 17 – 18, 2018Parks Canada
View on map
Archived · expired 8 years ago

Avalanche danger

Tue
Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
Open full map

Highlights

The natural avalanche cycle was tapering off Sunday afternoon. However, it is still primed for human triggering and forecasters expect the danger to return to high with an incoming system starting Monday night.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–2.5
    Up to 50cm of recent snow along with strong winds will have created storm slabs and wind slabs at all elevations. These slabs are still reactive to skier triggering. Ice climbers pay attention to overhead hazard.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–3
    The mid and lower portions of the snowpack are weak and are now overloaded with critical levels of snow. We expect avalanches to step down to this deeper layer.

Snowpack Summary

40 - 60 cm of snow since Dec 10 forming a storm slab over facets and surface hoar. New windslabs are common on lee (mostly east) aspects. The lower snowpack is weak and facetted with some avalanches running to ground.

Avalanche Summary

Numerous natural and skier or explosive triggered avalanches over the past few days up to size 2.5 have been reported and observed. Avalanches may run further down slope than expected, so be cautious of overhead hazard.

Confidence

Intensity of incoming weather systems is uncertain on Tuesday

Weather Forecast

Expect temperatures to rise to slightly above zero at valley bottom on Monday as another moderate system tracks through the forecast region. Temperatures will drop slightly into Tuesday as up to 20cm is deposited by the end of the day. Wind is expected to be moderate from the S/SW throughout Tuesday.

Regions covered