Avalanche forecast

Jasper

Jan 19 – 20, 2013Parks Canada
View on map
Archived · expired 14 years ago

Avalanche danger

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

Highlights

The declining avalanche danger ratings depend on the cooler temperatures in this weekend's weather forecast.  Danger ratings will rise on Monday with predicted rain and warming temperatures.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–3
    Hard to soft wind slabs have developed on lee aspects.  Numerous full depth natural slab avalanches have been observed on thin, steep, lee slopes in the alpine.  Wide propagations can be expected.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2–3
    Wind slab avalanches primarily in the alpine, have triggered this weakness. These avalanches have gained significant mass as a result. This situation will more likely occur in shallow snowpack areas.

Weather Forecast

Temperatures will begin a slight cool down on Saturday.  Moderate to strong ridge top winds will continue.  Light precipitation can be expected with broken skies.

Snowpack Summary

Extreme NW winds have stripped alpine and tree line fetch zones.  Hard to soft wind slabs are present on all lee slopes, predominately tree line and above.  In thin areas, these slabs are sitting on weak basal facets.  Below tree line, the old storm snow is moist and will consolidate with cooling temperatures, over a rotten base of facets.

Avalanche Summary

In the area around Whistler's, numerous full depth natural slab avalanches have been observed on thin, steep, lee slopes in the alpine.  We are seeing wide propagation to size 3 from continued NW wind loading.  These avalanches are running far in paths with steep run outs.   

Confidence

Freezing levels are uncertain on Saturday

Regions covered