Off Piste Snow Report – N French Alps – Week starting 21 December 2024
Significant snowfall expected Sunday and Monday, making for an excellent start to the Christmas week!
Up to now, the off-piste snow pack has been quite thin for the time of season (20 Dec), even though we’ve been able to ski down to 1500 m or so.Srong winds have often blown the snow off completely in exposed areas, compressing and hardening the snow in others. In more sheltered spots, particularly gullies, there may be 15 cm or so of light powder. It’s a real mixture of conditions at the moment.
Even though a slope may have looked invitingly white, there have been plenty of ‘sharks’ lurking, in the form of rocks lying on or just below the snow surface. We’ve heard of some bad injuries where off-piste skiers trying to find clean tracks have hit hidden rocks. (This brings to mind Michael Schumacher’s accident – it happened this time of year in a similarly thin snowpack). We hate seeing accidents like the ‘Park ‘n’ Fly” in the video below.
This should hopefully improve over the next few days, with predictions of 40 cm to 100 cm of fresh snow from the early hours of Sunday through to Tuesday morning. These significant amounts of snowfall, along with high winds, will come with a high risk of avalanche (likely to be 4 out of 5) in the 48 hours during and after the storm (see below).
Avalanche Bulletin
Avalanche danger ratings for the N French Alps on Sat 21 Dec by Meteo France. We expect this to rise to 4/5 in most places on Sun and Mon
At the time of writing this report (20 Dec – the last day of Autumn) the current avalanche danger level is a 2/5 below 2200 m, and 3/5 above that on the European scale. However, after the heavy snowfall expected from Saturday night, accompanied by strong W winds, we expect it to rise to a 4/5 on Sunday, probably into Monday and possibly even Tuesday in most of the Northern French Alps especially above 2200m. Winter is seriously arriving with a vengeance!
The current avalanche forecast and observation shows a lot of windslab created from the fresh snow of the last snowstorm (this past Friday-Saturday). This fresh layer of snow has come down directly on a fairly weak layer of facets. In addition, deeper down in the snowpack are some persistent weak layers of cohesionless snow which have formed over the last few weeks, particularly on higher altitude north’ish-facing slopes above 2200 m.
The sizes of slabs observed are mainly 1, some pushing into size 2, the forecast tells us not to rule out the possibility of a 3. And with the new storms forecast, we could see some impressive size 4. For the avalanche size scale see here .
‘Risk Reduction’ measures do not have much impact on reducing risk/danger to us with size 4 avalanches. See the HAT “Safety is Freedom Pocket Guide” for a better understanding of the impact of risk reduction.
Lower altitudes also have a weak layer present, but it is less significant (due to melting, refreezing and solidifying in the slightly warmer temperatures).
Weather forecast : Sat 21st to Thurs 26th Dec from Meteo-Alpes
SAT 21st: A bright day, especially in the east of the N French Alps. Clouds beginning to thicken later in the day. Snowfall during the night, down to 800 m. Light to moderate NW wind.
SUN 22nd: Big snowstorms, with very solid and persistent snowfall all morning. A slight lull in the weather around lunchtime, followed by a new weather front rapidly coming in from the north during afternoon, bringing more snowfall down to 600 m altitude. Strong NW wind at altitude.
MON 23rd: Snowfall continuing, maybe even intensifying as the day goes on. Snowing down to 500 m. Moderate NW wind. Expected amounts of snow from Saturday to Monday evening at different altitudes:
900 m : 15 to 25 cm, even 30 cm in places.
1500 m: 30 to 50 cm in the more S part of the area, 60 to 70 cm elsewhere or even 80 cm in Beaufortain/Haute-Tarentaise/Mont-Blanc.
Above 2100 m: 50 to 70 cm in Haute-Maurienne 60 to 80 cm in Oisans/Vercors, 75 to 90 cm elsewhere or even 1 meter to 1 meter 20 in Lauzière/Nord-Belledonne/Beaufortain
TUES 24th: Much calmer – snowfall rapidly clearing up in the morning. Sunny in the afternoon.
WED 25th & THURS 26th: Beautiful sunny days, with temperatures slightly milder; at least on the S facing slopes.
FOLLOWING: Dry and sunny
Safety is Freedom!
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Check out our 12 minute overview of the HAT Framework method and the Essentials Talk entitled, “Safety is Freedom Pocket Guide” on Video. It contains the key points that you need to know and to apply in order to keep things acceptably safe off-piste and ski touring, and to have more fun with or without a professional!
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