Avalanche forecast

Northwest Coastal

Dec 24 – 25, 2013Avalanche Canada
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Avalanche danger

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

Significant snow and rain will likely result in a large and destructive avalanche cycle.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–4
    The snow pack will see another heavy load tomorrow with heavy snow fall and rising freezing levels. Travel only in gentle well supported terrain free of overhead hazard.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    3–6
    The only terrain suitable for back country travel tomorrow is very gentle terrain free of overhead hazard.

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Synopsis:  A return to a heavy precipitation pattern is expected as the North Coast feels the brunt of a strong Pacific frontal system. Tonight and Wednesday: Heavy snow turning to rain: 30 to 40cm overnight with another 20 to 30cm Wednesday.  Freezing levels: 800m rising to 150m Wednesday morning.  Strong to extreme ridge top winds from the south.Thursday: Heavy precipitation.  Freezing levels: between 1500m to 2500m.  Strong to extreme ridgetop winds from the south.Friday: Periods of snow:  Freezing levels falling.  Winds forecast to diminish from the southwest.Special Notice: Our radar has just picked-up what appears to be a flying sleigh. Our forecasters believe the sleigh belongs to Santa as it is being pulled by at least 8 reindeer. The sleigh is now in the far north of the province at the 2000m elevation and is currently headed south. More information will be posted as it becomes available.

Avalanche Summary

The peak period of natural activity for the last storm cycle seems to have passed although explosive control continues to produce size 2 avalanche in the storm snow.

Snowpack Summary

The weekends storm brought between 50 to 90cm to the region. With lots of snow available for transport strong westerly winds have likely loaded lee features at upper elevations. In many places these winds slabs sit on top of touchy surface hoar from December 22.. The mid pack features several persistent weak layers that at this point have likely gained strength. The most noteworthy of theses may be the early December surface hoar and crust found in the top 100cm in areas with a shallower snowpack where it could still be a player. Below this the mid pack is composed of deteriorating layers of old facets and crusts. A significant basal facet and crust combo lingers near the ground and is most prevalent on NW - E facing aspects at the upper TL and alpine elevations.

Regions covered