By Henry's Avalanche Talk. Andreas Bjorklund photo (Wet snow avalanche which happened at 15.30 on 4 April in Val d'Isere)
Off Piste Snow ConditionsThe snowpack has become very wet and heavy due to the warm temperatures, lack of freeze and rain on slopes facing all directions, particularly those below 2500 m, but even higher on S'ish facing slopes.
It's definitely worth venturing out early, even when it looks grey and murky at resort level. There is still some pretty good snow above 2500 m on N facing slopes, due to the frequent top-ups of fresh snow above that altitude. This fresh snow is quickly melting and heavy as soon as the sun comes out, though, becoming more difficult to ski as the day goes on - even by mid-day up high if the sun comes out.
Snow StabilityWe really need some cold temperatures and refreeze to help consolidate the snowpack. Unfortunately, this does not seem very likely at the moment. As a result of the lack of re-freeze at night, the rain and the old rotten snowlayer from December (at the bottom of the snowpack), Avalanches of heavy, deeply humidified snow, often taking the snow right down to ground level, have been occurring during the night as well as the day. The frequency of these avalanches increases as the day goes on and temperatures rise. The large one on Andreas's photo on our blog post occurred at 15.30 earlier this week on the Marmottes off-piste area (North West facing - 2400 m) coming down from Solaise above Val d'Isere. Strong SW to SE winds in very high mountain areas have formed areas of surface windslab, which could be triggered by the weight of just one skier passing by. The avalanche risk has recently been at around 3, mainly because of all these slides of heavy humidified snow in the warm temperatures. See our HAT advice for what all the avalanche danger ratings mean: http://www.henrysavalanchetalk.com/avalanche-forecasts-danger-rating.
Tips of the WeekBe careful of all steep slopes especially from mid-morning onwards and below 2500 m after a light freeze.. or non existant freeze at night. The whole slope could let loose (North'ish facing slopes could go at any time this coming week, we believe because of the saturated snowpack combined with the old rotten layer from December).
Changes in snow stability will occur when there is a change in the weather (such as high winds, snowfall, etc). Keep checking our Facebook page to get our latest updates: www.facebook.com/HenrysAvalancheTalk
Check the daily avalanche bulletins on this link: http://www.meteofrance.com/previsions-meteo-montagne/bulletin-avalanches, by clicking on the mountain area you're in.
We'll be updating our blog as much as possible if conditions start to look unstable, or if we have some nice photos from a great ski on www.henrysavalanchetalk.com/blog also on Twitter @HenryOff_Piste Keep checking our facebook page for updates too: www.facebook.com/HenrysAvalancheTalkread more