Avalanche forecast

Northwest Coastal

Mar 31 – Apr 1, 2014Avalanche Canada
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Avalanche danger

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

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–4
    While the old hard wind slabs are unlikely to be triggered at this point, fresh shallow wind slabs may be found immediately lee of ridge crest and mid slope features.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    3–6
    At this point the deep persistent weak layers would likely require a specific trigger like cornice fall, a surface avalanche in motion, or a rider finding the sweet spot, to be activated.

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Tuesday

Weather Forecast

Synopsis: The ridge of high pressure will continue dominate the weather through Tuesday before breaking down as frontal system makes landfall Wednesday.Tuesday: Freezing Level: 500 - 1200m Precipitation: Nil; Wind: Treeline: Light, SW | Ridgetop: Moderate, NWWednesday: Freezing Level: 400m - 1100m; Precipitation: 2:6mm - 2:10cm; Wind: Treeline: Light, SW increasing to moderate SE | Ridgetop: Strong, SWThursday: Freezing Level: Valley Bottom - 700m; Precipitation: 2:5mm - 2:10cm; Wind: Treeline: Strong, S | Ridgetop: Strong:Extreme, SW

Avalanche Summary

Avalanche activity on Sunday was limited to point releases from steep terrain.

Snowpack Summary

It's starting to feel like spring in the NW. Valley temps are creeping into the double digits during the day, and there are reports of the top 15 cm of the snowpack becoming moist during daytime heating.The last significant shot of snow was on March 27th, 10 - 15 fell on March 30th. This new snow rests on top of a haggard old surface composed of old wind slab, melt freeze crust, and faceted old snow. Ongoing melt freeze cycles will likely help to heal any surface instabilities.The early March layer can be found down 75 - 100cm and is composed of facets/surface hoar on shady aspects and facets/crust on southerly aspects. I suspect this layer has been the culprit in the human triggered avalanches from March 27/28 that are being reported on the Balktalk Facebook Page.The early February crust/facet/surface hoar combo is down 150 - 200cm, and I suspect it's gone dormant for now.

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