Avalanche forecast

Northwest Coastal

Feb 18 – 19, 2014Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    2–5
    Close to a metre of highly reactive storm slab is now sitting on a variety of weak layers, facets, surface hoar and decomposed wind slab. Significant potential for remotely triggering an avalanche below or adjacent to start zones exists.

Confidence

Fair - Forecast snowfall amounts are uncertain

Weather Forecast

Tuesday evening:  A Pacific frontal system tracking mostly across the South Coast will affect southern portions of the NW regions. Generally unsettled conditions are expected for Wednesday before another weak system impacts the central coast on Wednesday night or Thursday morning. Possibility of 10 to 209 cm  in the Mtns. just east of the coast.Wednesday: Mostly cloudy, light locally moderate snowfall, some parts of the forecast area may receive 10-15cm of snow, freezing levels around 400m, ridge top winds 20-30km/h SW-WThursday: Freezing level at or near valley bottom. Snowfall amounts, 5-10cm,  ridge top winds from the W-NW 30-50km/h Friday:  Freezing level around 100m. Light to locally moderate precipitation, some parts of the area may receive 10 to 15cm of snow, ridge top winds light to moderate from the south.

Avalanche Summary

Numerous reports of size 1.5 to 2.5 natural avalanches, as well as skier remote avalanches up to size 2

Snowpack Summary

Parts of the forecast region have received over 1.5m of cumulative storm snow which has now settled into a slab with a typical thickness of 60-90cm. This storm slab overlies a variety of facets, surface hoar, crusts, hard wind press, or any combination of these. Widespread whumpfing, cracking, natural avalanche activity and remote triggering at all elevations  are a strong indication of poor bond between the new snow and these old surfaces. Snowpack tests show easy, sudden planar results with good propagation propensity.

Regions covered