Avalanche forecast

Northwest Coastal

Feb 23 – 24, 2016Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Widespread wind effect has been reported from the alpine. The best and safest riding can probably be found on sheltered slopes at treeline and below.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    3–6
    everal buried weak layers remain a concern depending on where you are in the region. In thin snowpack areas large avalanches can be triggered from thin spots or by heavy loads such as a cornice release or smaller avalanche.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–3
    Lingering storm slabs may be found on steep unsupported slopes and in wind loaded alpine features.

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

WEDNESDAY: partly cloudy with flurries possible in the afternoon, light to moderate southerly winds, freezing level rising to 1000m through the day. THURSDAY: snow overnight and through the day (up to 10cm around Terrace and 5cm further inland), moderate to strong southerly winds, 1500m freezing level. FRIDAY: snow continues (another 15-20 for Terrace, 10 inland), moderate to strong southerly winds, 1500m freezing level.

Avalanche Summary

A couple of natural and skier triggered storm and wind slab avalanches with limited propagation were reported over the last couple of days. Cornices are large and fragile. Northeast of Bell 2 a natural avalanche at treeline was observed to have stepped down to the early January surfaces hoar on Sunday. While this avalanche technically occurred in the Northwest Inland region it is a good reminder that this layer remains a concern, especially in the thinner snowpack areas.

Snowpack Summary

The upper snowpack continues to settle and gain strength although some lingering mid-storm instabilities are still showing up in snow profiles. A thin crust may cap moist snow at lower elevations and on slopes that see direct sun. Recent winds have formed wind pressed surfaces in exposed terrain and loaded lee features. 40-100cm of snow now sits above a melt freeze crust buried on February 12th. This crust extends up to about 2000m. Although the snow above is bonding well to this crust in most places, recent snow pit tests northwest of Terrace produced failures on or in facets just below this layer under moderate to hard loads. Below this, a layer of surface hoar buried late in January remains a concern in thinner snowpack areas in the east and north of the region. The snowpack in these areas may also sit on a weak base of facets near the ground.

Regions covered