Off Piste Snow Report : 19th – 23rd December 2015

by Henry's Avalanche Talk Extended Weather Forecast (as reported by Météo-France Savoie) for Savoie and the N French Alps:

A high pressure weather system is in place, with mild temperatures and plenty of sunshine. Hopefully some very light snow on Monday evening, but no significant amounts forecast.

Saturday 19th: Sunny. Light W to NW winds. Temperatures rising as the day goes on, becoming very mild in the afternoon (0° at 3300 m).
Sunday 20th & Monday 21st: Sunday: Sunny and mild. Monday: Following a bright morning, the day will slowly cloud over with very light precipitation into the evening and night. This will hopefully fall as snow at 2000 m, and down to 1500 m as temperatures drop.
Tuesday 22nd & Wednesday 23rd: Tuesday: After a cloudy start, the sky will clear and it will be sunny for the rest of the day. Winds turning southerly, with gusts of 40 to 50 km/hr. Wednesday: Alternating between sunshine and cloud. Both days continuing very mild.

Off Piste Snow Conditions

We need some significant snowfall as the snowpack's getting pretty thin now, with plenty of rocks and grass around. In the 'Haute Tarentaise' area of Savoie: At altitudes above 2500 m, off-piste depths are around 50 cm on N facing slopes, 25 cm on S facing slopes. At 2000 m, off-piste snow depths are around 30 cm on N facing slopes, but sometimes no snow on more S facing ones.
By walking and persevering, we are often still able to find pockets of nice cold snow in sheltered gulleys and couloirs. On N facing slopes, the snow is often quite nice to ski at the moment, and we're finding areas of old 'sugar' snow. This will become a dangerously weak layer when we get a good layer of fresh snow, but is quite pleasant to ski at the moment.
On sunny SE to SW facing and lower altitude slopes, the surface snow is humidified, usually crusted first thing in the morning following overnight refreeze, then quickly softening up as the day goes on... In sum, not very nice!
The visibility continues to be excellent with our continuing days of wall to wall sunshine.

Snow Stability

Until we get any significant snowfall, the avalanche risk remains low below 2500 m, and slightly higher above that. It's estimated at around 1 to 2 out of 5 by the forecasters (we at HAT believe that even 2 is a bit on the high side at the moment). See our HAT advice for what all the danger ratings mean: http://www.henrysavalanchetalk.com/avalanche-forecasts-danger-rating.
Recent snowpack analyses have shown a shallow snowpack (less than 50 cm deep) consisting mainly of cold snow with surface layers composed of faceted grains - snow that lacks resistance, what we referred to above as 'sugar snow'. In some places this 'sugar snow' is starting to make up the entire snowpack (especially on North'ish facing slopes avove 2200 metres). This will constitute a very weak layer when the next significant snowfall arrives.
AT HAT we're predicting that by the time any significant snowfall comes, most of the snowpack will be made up of these faceted grains, cohesionless 'sugar snow' (..'depth hoar', cup 'shaped crystals', 'goblets'...), at just about all altitudes and aspects. This will make just about all slopes of 30° (about steep red run to black run steepness) or steeper dangerous.
For now, the low danger refers to a very few areas of older persistent, hardened, partially buried, windslab above 2500 m. These are more unstable on steep NE to NW facing slopes and could release in a confined 'localised' are if a group of skiers passes together on top of it .

Tip of the Week

Until we get any significant snowfall, the main off-piste risk continues to be the rocks and other obstacles poking through the snow or hidden below the surface. However, anticipate that when the next snow does eventually come, the snowpack's going to become very unstable, much like last year.. and the year before in December/early January.
The detailed daily avalanche bulletins are now starting to appear daily. You can check them on this link: http://www.meteofrance.com/previsions-meteo-montagne/bulletin-avalanches, entering the mountain area of your choice.
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 and Google+ and Facebook
Ride Hard !! Ride Safe everybody
Wayne Watson photo
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