Avalanche forecast

South Rockies

Jan 16 – 17, 2012Avalanche Canada
View on map
Archived · expired 15 years ago

Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
Open full map

Highlights

Locally heavy snowfall is possible, which could bump the danger to considerable at treeline on Tuesday in specific areas. Wednesday and Thursday's forecast is highly uncertain. Check in daily for updates.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–4
    New wind slabs are likely to form quickly as the the wind picks up again, due to the amount of available loose snow.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1–6
    A buried surface hoar layer in the top metre of the snowpack continues to be a concern. Although it has become stubborn to trigger, the consequences are high. It's most likely to be triggered from shallow rocky areas on a slope.

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2
    Loose dry new snow will sluff easily in steep terrain. It could knock you off your feet or carry you into a terrain trap.

Confidence

Poor - Timing, track, or intensity of incoming weather is uncertain on Wednesday

Weather Forecast

Tuesday: 5-10cm snow. Strong to gale south-westerly winds. Freezing level at valley floor.Wednesday/Thursday: Weather models show very different outcomes. Anything's possible - from dry conditions to moderate (locally heavy) snowfall, with strong westerly winds and a slight rise in temperature. Confidence is poor. Check in tomorrow for an update.

Avalanche Summary

We haven't had any reports of new avalanche activity.

Snowpack Summary

Up to 30cm recent snow fell with little wind. This overlies older wind slabs, which appear to be well bonded. New wind slabs are likely to form quickly at the first sign of wind, as plenty of loose snow is available for transport.Besides new storm/wind-related concerns, the layer we're still watching in the region is a surface hoar layer buried in early December. It's down about 85cm in the Flathead and exhibits hard, sudden planar/full propagation results, meaning that's it's stubborn to trigger but could create a large avalanche if triggered.At the bottom of the snowpack a variable facet/crust/facet sandwich is located with depth hoar up to size 5mm below the crust, and facets size 2mm above. There has been little in the way of recent activity on basal layers.

Regions covered