Avalanche forecast

South Coast

Dec 1 – 2, 2011Avalanche Canada
View on map
Archived · expired 15 years ago

Avalanche danger

Sat
Sun
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
Open full map

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–3
    Reverse loading is possible with forecast NW winds late Thursday and Friday. Watch for hard or soft wind slabs in exposed terrain on a variety of different aspects.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–5
    Weak layers of facets and depth hoar may be lurking deep in the snowpack. Be very cautious in shallow snowpack areas where triggering deeper weaknesses is more likely.

Confidence

Fair - Due to limited field observations

Weather Forecast

A weak cold front should cross the region overnight on Thursday bringing gusty NW winds and a chance of light precipitation. The freezing level should drop to around 300m. The ridge of high pressure rebounds on Friday bringing dry and mainly sunny conditions to the South Coast for the next few days. We could see a temperature inversion develop by the weekend with highs of 5 or 6 degrees between 1500 and 2500m on Saturday, and 1500 and 3000m on Sunday.

Avalanche Summary

No new reports of avalanche activity in the region. Although it may be harder to trigger some of the deeper weaknesses in the snowpack, if you do, the resulting avalanche could be very large and destructive.

Snowpack Summary

Up higher, wind slabs and lingering storm snow instabilities still exist. There is a solid rain crust, down 15-30cm below 1800m, which has greatly reduced the likelihood of avalanches at lower elevations. A surface hoar layer has been observed down approximately 45cm in the Duffey Lake area. A facet layer near the base of the snowpack continues to give sudden collapse, ("drops") results in snowpack tests. Continued caution is recommended in shallow snowpack areas (lots of rocks or small trees poking through), especially on sun exposed slopes if the sun has any kick, and on any slope that has not recently released.

Regions covered