Alpes du Sud
Embrunals-Parpaillon
Avalanche Problems
Persistent weak layers + No distinct problem
1
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
N Indice de risque faible.
encore une petite humidification en versants bien ensoleillés d'altitude. Départs ponctuels de neige humide possibles près des rochers, taille 1.
Outlook
Constant avalanche danger
Snowpack & Weather
Snowpack
Situation avalancheuse typique
couche fragile persistante
rares plaques dures résiduelles. Localisées en versants peu ensoleillés d'altitude supérieure à 2400 m environ, elles sont difficiles à déclencher par un seul skieur et leur
rupture ne provoque que de petites avalanches (taille 1). Formées sous l'effet du vent fort en fin de semaine dernière, ces instabilités sont souvent identifiables en surface
dans les zones d'accumulation par le vent en altitude. Une avalanche de plus grande ampleur (taille 2, moyenne) n'est pas exclue en cas de sollicitation en cascade d'une
couche fragile enfouie dans un large secteur nord au-dessus de 2400 m.
Départs spontanés : encore une petite humidification en versants bien ensoleillés d'altitude. Départs ponctuels de neige humide possibles près des rochers, taille 1.
Outlook
Tendance du dimanche 14 décembre
Indice de risque faible
oursuite d'un temps calme et ensoleillé, un
u moins chaud, vent de sud modéré en
titude l'après-midi. Risque faible.