Alpes du Nord
Haute-Tarentaise
Day Risk Profile
Avalanche Problems
Persistent weak layers + No distinct problem
2
Field notes
Persistent weak layers
Persistent Snowpack layer in which the crystals are poorly bonded and the layer has the potential to fail. Typical crystals in dry weak layers causing avalanches are : precipitation particles; surface hoar; faceted crystals; hollow crystals; graupel. Generally >1mm in size, loose grains with few bonds Wet weak layers can be formed by all snow crystal/grain types.EAWS glossary are very challenging to recognise. Distinctive noise (resembling a “whumpf” sound) occurring when a weak layer beneath a slab collapses. The air of the weak layer is forced outside the snowpack, with the resulting whumpf sound being heard. The sound usually indicates an unstable situation and can be accompanied by surface cracking. A whumpf is a clear avalanche alert.EAWS glossary sounds and shooting cracks are typical when present, but you can have a serious weak layer with no warning signs at the surface. Knowledge of how the Snow deposited on the ground in a multiplicity of layers.EAWS glossary has evolved is essential. SLF's travel advice is direct: travel conservatively, avoid terrain where the consequences of being caught are large, and treat the history of weather and snow as more important than what you can see today. Read the full bulletin.
No distinct problem
SLF uses this label when no single problem dominates the assessment, often on lower-danger days. It doesn't mean conditions are safe: any avalanche type is still possible, and normal caution applies. On stable days this is usually a signal to enjoy the mountains with general awareness; on less-stable days where the assessment is still inconclusive, it's a signal to be cautious specifically because there's no clear pattern to follow.
Avalanche Activity
MANTEAU PLUTÔT ASSEZ BIEN STABILISÉ
quelques plaques de fond dans la tranche d'altitude 2100/2600 m. Surtout dans les versants SE, S, SO. Possibles à toute heure, surtout l'après-midi. Taille
2.
rares plaques dans la neige restée froide (Direction in which a slope faces as indicated by compass direction of the fall line; i.e. a north slope faces in a northerly direction.EAWS glossary poudreux ou ventée) , au-dessus de 2100/2200 m, principalement en versants E/N/O. Elles sont
localisées dans les zones d'accumulation créées par le vent de Sud. Elles reposent sur une couche fragile persistante, irrégulièrement répartie
Observables : changement de qualité de neige sur une courte distance, alternance érosion/accumulation. woumf. Taille 1 à 2 (petite à moyenne).
Outlook
Constant avalanche danger
Snowpack & Weather
Snowpack
Situation avalancheuse typique
couche fragile persistante avalanches de fond
Déclenchements provoqués : rares plaques dans la neige restée froide (Direction in which a slope faces as indicated by compass direction of the fall line; i.e. a north slope faces in a northerly direction.EAWS glossary poudreux ou ventée) , au-dessus de 2100/2200 m, principalement en versants E/N/O. Elles sont
localisées dans les zones d'accumulation créées par le vent de Sud. Elles reposent sur une couche fragile persistante, irrégulièrement répartie
Observables : changement de qualité de neige sur une courte distance, alternance érosion/accumulation. woumf. Taille 1 à 2 (petite à moyenne).
Départs spontanés : quelques plaques de fond dans la tranche d'altitude 2100/2600 m. Surtout dans les versants SE, S, SO. Possibles à toute heure, surtout l'après-midi. Taille
2.
Outlook
Tendance du lundi 15 décembre
Indice de risque limité
u de changement même si attention au
nt qui pourrait très localement créer de
ouvelles plaques.