There has been lots of recent avalanche activity after the rain/snow of Thursday evening through Saturday morning. The rain-snow limit of 2400m was not good for the quality of snow, but a huge help in stabilizing a fragile early-season snowpack. The best ways to remedy a persistent weak layer is through: rain (and/or a massive warming spell), purging (like in images here of recent activity) and skier compaction…When it rains it snows… at least somewhere up above. Over a metre and a half of snow in some places at around 2800/3000 mètres in many places in N French Alps according to recent piste patroller accounts.
Several days of heavy rain in the N French Alps has taken its toll on the snow, particularly off-piste and on slopes below 2200 m. When the sun eventually came out on Saturday, it revealed plenty of recent avalanche activity (as photoes in this report show).
It’s been very mild for the time of season, so unfortunately any precipitation below about 2400/2600 m fell as rain. And did it rain! Even the locals had trouble remembering such a prolonged duration of rain.
Of course, when it rains, it also snows, at least somewhere at high altitude. According to piste patroller accounts, over 1.5 m of snow fell at around 2800/3000 m in many places in N French Alps. Sadly, though, many mid and lower-altitude resorts have been badly hit by these mild conditions, melting and rainfall.
The weather next week looks a lot calmer, but with temperatures remaining milder than we’re used to for the time of season. Possible light snowfall is on the forecast for Monday evening/night, which would be very welcome.
Unfortunately the recent rain has washed away a lot of the snow, particularly below 1800 m.
Best quality snow is at high altitude above 2500 m, particularly on the glaciers. Conversely, there’s still a dangerous weak layer in the snowpack on these higher altitude slopes, which haven’t been subjected to the stabilising effect of the rain and melting, followed by subsequent refreezing on the lower slopes.
Here’s the Meteo France image of off-piste snow depths for the Haute Tarentaise on 25th December 2022, with depths fairly normal for the time of season for altitudes above 2300/2500 m, but much less than usual for lower slopes.
At the moment the off-piste snow is what we would term ‘skiers’ snow’, which means it’s not the easiest! It’s quite heavy and humidified, even at mid-altitudes of 2200 m or so.
Calmer weather is forecast this coming week, although it’s remaining unseasonably mild. We may hopefully get a bit of fresh snow on Monday, and possibly later in the week. Fingers crossed.
The pisted snow which has been groomed and packed down is, to be honest, much easier to ski than much of the off-piste at the moment.
Lots of recent avalanche activity after the rain/snow of Thursday evening through Saturday morning.
These photos are a great visual representation of what an avalanche risk 4 (maybe a very high 3) looks like. There’s a shocking amount of recent natural avalanche activity as the mountain purges itself following the last few few days of milder temperatures, accompanied by rain/snow and melting.
The good thing about the recent warming episode is that it’s a great way to sort out the problem of the fragile layer in the snowpack which we’ve been banging on about over the last 3 weeks. The rain/snow limit of 2400m was not good for the quality of snow, but a huge help in stabilizing the fragile early season snowpack. The best ways to remedy a persistent weak layer are through: rain (and/or a massive warming spell), purging (like in these images of recent activity) and skier compaction.
Making the most of the skiing at high altitude on low angle slopes. Wayne Watson photo
Avalanche Bulletin 25th December 2022
Current danger rating in Haute Tarentaise
The bulletin reports a considerable danger rating of 3 above 2500m, on slopes facing all directions and a moderate risk of 2 below 2200 m
The reason for this discrepancy is that the high altitude slopes above 2500 m were the ones that received snow instead of rain. The lower slopes, where it rained in droves, are becoming more more stable thanks to the rain/warming/melting, followed by light refreezing (with a solidifying effect).
Christmas Weather forecast 25th to 31st December (and indication beyond)
The sun is back for Christmas! Looks like a lot of sunshine to enjoy. It is not clear when we will get a new dump of snow to refresh the heavy moistened snow that exists below 2500m. Piste skiing looks like a lot of fun for holiday makers enjoying the festive season
SUNDAY, 25th DECEMBER
Sunny with temperatures unseasonably mild. 0°C at 3000 m first thing in the morning, and getting even warmer as the day goes on. SW to W wind, 20 – 50 km/hr at 3000 m.
MONDAY, 26th DECEMBER
A weak sun, behind thin high cloud in the morning. Clouding over in the afternoon with light snowfall above 1600 m or so (possibly 5 to 15 cm). Wind turning NW, 50 km/hr at 3000 m. Temperatures a little lower, 0° C at 2000 m.
TUESDAY, 27th DECEMBER
Brightening up as the morning goes on. Light N to NW wind. 0° C at 1600 m, rising to 2000 m as the day warms up.
WEDNESDAY, 28th DECEMBER
Veiled sunshine in the mountains. Cloud thickening as the day goes on. 0° C at around 2500 m.
THURSDAY, 29th DECEMBER
A cloudy day in the mountains, with possible light snowfall 1600 m. W wind, 50/60 km/hr at high altitude. 0° C at 1900 m.
FRIDAY, 30th & SATURDAY 31st DECEMBER:
Uncertain. W to SW wind. Possible snowfall above 1600 m on Friday. Becoming drier and and remaining from Saturday onwards.
Tip of the Week
The best quality snow can be found at higher altitudes above 2500 m, and you can still find some great skiing here. Be aware though that at these higher altitudes, where it snowed rather than rained, the persistent weak layer in the snowpack still exists. These very high slopes did not benefit from the stabilising effect of the rain or massive warming and then refreezing, as did the lower slopes. Continue to be very cautious when skiing up high.