Avalanche forecast

Northwest Coastal

Apr 9 – 10, 2018Avalanche Canada
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Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Rising freezing levels and rain are the main concerns for the next few days. Watch for moist or wet snow, the warming trend has produced several large loose, wet avalanches in recent days.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2.5
    Recent storm snow may become unstable with rising freezing levels and rain. Once moving a loose wet slide may have the potential to trigger a slab on a deeper weak layer.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

TONIGHT: Mostly cloudy. Precipitation trace. Ridge wind moderate, south. Alpine temperature near 0. Freezing level rising to 1600 m.TUESDAY: Cloudy, rain changing to snow. Precipitation 10-15 mm. Ridge wind strong to extreme, southeast. Alpine temperature near 0. Freezing level 1600 m.WEDNESDAY: Mix of sun and cloud. Ridge wind moderate to strong, southeast. Alpine temperature near 0. Freezing level 1500 m. Rain or snow beginning in the evening.THURSDAY: Mix of sun and cloud, snow ending. Accumulation 10-15 cm. Ridge wind moderate, south. Alpine temperature near -2. Freezing level 1200 m.

Avalanche Summary

Northern parts of the region reported that; warming on Sunday produced a natural, loose, wet avalanche cycle up to size 2 on solar aspects and in steep terrain at treeline and below.Last week, the Shames area saw a widespread natural cycle up to size 3 on solar aspects as a result of Friday's storm. See recent MIN report. While further north only isolated wind slab and loose, wet activity was reported. Read MIN report.On Thursday northern parts of the region saw a widespread natural avalanche cycle triggered by strong to extreme wind loading event in the alpine. There was also a report of an icefall triggered size 2.5 slab avalanche that failed on the mid-March interface, northwest of Meziadin Lake.

Snowpack Summary

Rain and warming have created wet or moist snow within the top 10-20 cm of the snowpack, with little to no overnight re-freeze. Only high alpine north aspects are still harboring dry snow. In the south of the region, two layers of surface hoar are buried approximately 70-100 cm deep. The layers are most prominent on north to east aspects and were buried early-March and mid-March. In the north of the region, these layers are around 40 cm deep.Bellow these March layers the mid-pack is generally well-settled and strong. However, shallower parts of the region, such as the far north, have weak sugary facets near the bottom of the snowpack.

Regions covered