Bulletin d’avalanche

Jasper

Feb 8 – 9, 2018Parks Canada
Voir sur la carte
Archivé · expiré 9 years ago

Danger d’avalanche

Fri
Sat
Alpin
4 · Fort
Limite forestière
4 · Fort
Sous la limite
3 · Marqué
Ouvrir la carte complète

Points saillants

25-35cm of storm snow expected overnight Wednesday will increase the Avalanche Danger and may require traffic interruptions Thursday for control work on Highway 93N. Maligne Lake Road will be closed Wednesday evening until Friday evening.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–2.5
    Windslabs were created over the last week with 40cm of snow and West winds. The incoming snow coupled with moderate West winds may build sensitive new storm / windslabs.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    2–3.5
    Field teams observed whumpfing and moderate test results Sunday and Monday in sheltered zones around treeline on these layers. Shallow areas are the most likely triggering locations in the alpine.

Weather Forecast

Warm, wet, pacific air is meeting cooler arctic air over the forecast area with snowfall intensifying overnight. This system may bring 25-30mm of precipitation with moderate winds and temperatures near -5C. The snowfall event is expected to last into Friday morning when a ridge dominates with cooler temps and blue skies into the weekend.

Snowpack Summary

Moderate SW winds will add the new snow to last week's windslabs in the usual lee locations. Mid-pack persistent weak layers, most notably Jan 7 surface hoar down 40-60cm and rotten Dec 15 facets sitting just below, remain the primary snowpack concern for larger avalanches.

Avalanche Summary

On Monday a sz 3 natural slab avalanche was observed from a thin snowpack area in the Maligne valley on the NE side of Proposal peak at 2500m. Notable avalanches this past week were generally windslabs in the alpine to sz 2.5 and a few persistent slabs in the low alpine and treeline elevation band.

Confidence

Forecast snowfall amounts are uncertain on Wednesday

Régions couvertes