Avalanche forecast

Northwest Coastal

Dec 22 – 23, 2015Avalanche Canada
View on map
Archived · expired 11 years ago

Avalanche danger

Thu
Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Open full map

Highlights

A period of benign weather means avalanche conditions will not change significantly. The best riding conditions can be found in sheltered areas, but be mindful of the surface hoar buried around tree-line.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–4
    Recent snow is slowly settling into a soft slab. Variable winds will have formed deeper slabs in lee features on east through northwest aspects at higher elevations.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    2–4
    A couple of buried weak layer of surface hoar should be on your radar. I would be suspect of steep unsupported slopes at tree-line unless I knew the layer did not exist or was now well bonded.

Confidence

Moderate

Weather Forecast

We're looking at a period of fairly benign weather leading into the weekend. There may be some isolated flurries although not significant accumulations of new snow are expected. An artic front just inland stretches almost all the way down the coast and will keep freezing levels at, or close to valley floor throughout the forecast period. Winds will be light and variable Tuesday and Wednesday before becoming moderate westerlies by Friday.

Avalanche Summary

Small loose avalanches have been reported in steep terrain in the alpine. There haven't been any reports of recent avalanche activity on any buried layers of surface hoar. However, I suspect that as the new snow continues to settle well start to see these layers wake up. It's difficult to predict when that will be with the slow incremental loading pattern we're dealing with

Snowpack Summary

Sustained snowfall over the last several days has apparently made for awesome riding conditions. Cool temperatures have slowed the settlement of this new snow although light but variable winds have formed pockets of fresh wind slab on east through north-west aspects at tree-line and in the alpine. The recent storms have been incrementally adding load to a couple of week couple of buried persistent weak layers that we're tracking. There is now 25-40 cm above the December 17th surface hoar, and 35-55 cm above the December 14th surface hoar. Snow pit tests on Monday produced sudden failures on both of these layers. The December 1st surface hoar is now down a meter or so depending on your area. The distribution of this layer is variable. In some areas, it may still be sensitive to human triggering and capable of wide propagations, in other areas it is non-existent or has gained significant strength. Conditions may be different close to Kitimat, where it looks like recent snowfall amounts may be a bit higher and temperatures a bit warmer.

Regions covered