Here is a quick look at the temperature inversion at the moment. 10 to 12C overnight at 1800 meters altitude whereas 1500 meters below in the valley the temperature rapidly sinks down to near freezing.
Many skiers have been surprised by this. Expecting hard snow and maybe spring conditions in the sunshine they have been confronted with knee deep unskiable mush. The risk of being caught by a full depth avalanche is also not to be ignored, especially ski touring where you are exposed for a long time while climbing.
Days for staying on piste, which is what we did yesterday at St Hilaire
This shot from Friday shows the wind sculpting of the snow
with some considerable cross loading on this slope.
When it cools down conditions should be a lot more stable below 2000-2400 meters. Some fresh snow is expected on Boxing Day (26th) at 900m but it is warming up again on the 27th with the snowline around 1600-1800 meters.