Avalanche forecast

North Rockies

Apr 18 – 19, 2023Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low

Highlights

Riders must manage various avalanche concerns that vary by elevation and aspect. Observe your local conditions and let that inform your terrain choices.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    With recent wind, and various amounts of new snow, anticipate fresh wind slab development. Watch for these wind slab pockets, primarily in steep north and east-facing leeward slopes.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2.5–4

    A weak layer of facets exists near the base of the snowpack. Thinner snowpack areas and areas with variable thick and thin coverage at alpine elevations is where this problem is most likely found. April's warming temperatures may gradually increase the sensitivity of this layer, especially in thin snowpack areas.

Confidence

Low

Avalanche Summary

No new avalanches have been reported since last week.

Snowpack Summary

On north aspects above 1800 m, recent snow is settling over old, sugary, faceted grains, now around 30-70 cm deep.

On solar aspects to mountain top, and north aspects to around 2000m the recent snow either overlies a widespread melt-freeze crust or there is a crust at the surface. Solar aspects are becoming moist in the afternoon, as are all aspects at lower elevations (around 1700 or 1800 m).

The middle of the snowpack is generally well-settled and strong. A weak layer of facets at the base of the snowpack remains a concern, primarily in alpine terrain with shallow or variable (thick and thin) snowpack depths.

Weather Summary

Tuesday night

Mostly cloudy with trace amounts of snow. Moderate south ridgetop winds. Treeline temperature around -5 C.

Wednesday

Mostly cloudy, with flurries and trace accumulation. Light to moderate south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 2000 m.

Thursday

Cloudy with scattered flurries. Light to moderate south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 2000 m.

Friday

Cloudy with scattered flurries. Light to moderate south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 2000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for fresh storm slabs building throughout the day.
  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
  • Be alert to conditions that change with elevation and sun exposure.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Regions covered