Boletín de aludes

Kootenay Boundary

Feb 27 – 28, 2014Avalanche Canada
Ver en el mapa
Archivado · caducó 13 years ago

Peligro de aludes

Sat
Sun
Alta montaña
3 · Notable
Límite del bosque
3 · Notable
Bajo el límite
3 · Notable
Abrir el mapa completo

Lo esencial

We are entering a 'low probability/high consequence' phase with a tricky persistent weak layer. Check out this new blog post on difficult decision making and current conditions.Avoid large, unsupported slopes, especially on north aspects.

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–4
    Older wind slabs still exist in many lee terrain features but are becoming harder to trigger. Some isolated areas may have thin, touchy wind slabs from more recent wind. Weak cornices also remain a concern in isolated areas.

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible - Likely
    Tamaño
    3–6
    Expect the deeply buried weak layers to continue to produce large and destructive avalanches. Many slopes are still primed for human triggering and remain a concern on all aspects and elevations.

Confidence

Fair

Weather Forecast

Unsettled conditions are expected for Friday before arctic air moves into the region Friday evening. On Saturday and Sunday, weak disturbance from the south will mix with the cold air and may result in light scattered flurries.Friday: Mostly cloudy with sunny breaks, scattered flurries 2-8cm, treeline temperature around -8C, ridgetop winds 15-25 km/h variableSaturday: A mix of sun and cloud, scattered flurries 2-4cm, treeline temperature around -15C, ridgetop winds 10-20 km/h NE, outflow winds at valley bottomSunday: Mostly cloudy with sunny breaks, scattered flurries 2-4cm, treeline temperature around -12C, ridgetop winds 30-50 km/h SW

Avalanche Summary

Wednesday saw natural activity up to size 3 on SE through SW aspects triggered by solar warming.  Also reported were two skier remote triggered avalanches sized 1.5 and 2.  These were both triggered from 5m away and were 70cm deep.

Snowpack Summary

The primary concern is a ~1m thick slab from the last series of storms that is sitting on a stubborn persistent weak layer consisting of facets, surface hoar, melt-freeze crusts, or any combination of these. This weak layer is widespread at all elevations and aspects. Recent test results are suggesting that the layer is still easy to trigger in some areas but may becoming harder to trigger in other areas. We are still receiving isolated reports of large settlements or whumpfing which suggests the layer still has the potential for large propagations. In many areas the layer has the potential to produce large, destructive avalanches. The phase we are now entering is referred to a 'low probability/high consequence' problem. Continue to use conservative terrain choices until you are sure the layer is no longer unstable in your local area. Variable winds from the southwest through north have created touchy wind slabs on leeward slopes and cross-loaded features. In wind-loaded areas, slabs up to 2m thick may overlie the persistent weak layer.On south aspects, a sun crust has formed on the surface. New surface hoar formation 5-10mm has been observed.

Regiones cubiertas