Lots of snow and big differences in the snow line

Our snow maps are showing red colors and there are some black spots appearing on the maps again. It’s an indication that we’re about to get another periode with lots of snowfall. But the big question over the next 72 hours is: what will the snow line do? But first a warning. Yesterday was the first bluebird day after a period of intense snowfall. Avalanches claimed the lives of two skiers and several people were injured. If you are you going off-piste go for the parts of the mountain that are less dangerous. You need to have the right knowledge for that. If you don’t have the right knowledge, hire a mountain guide! In this forecast:

• Short term: Wat will the snow line do?
• Colder after the weekend, southern Stau and northern Stau!
• Powder advice for the next couple of days

Short term: Wat will the snow line do?

Today will start sunny and it’s pretty cold, but a new front is coming in from the west. It will start snowing in the northwest of the Alps during the afternoon. You can expect 3-15 cm of freshies till Thursday morning and because it’s still pretty cold, the snow line will be at very low altitude. Things will be different on Thursday. A warm front is approaching the Alps from the west.

Because there still is a lot of cold air in the valleys, the snow line will stay at low altitude at first. This cold air doesn’t go away that fast from narrow valleys. Cold air is heavier, while warm air is lighter. But prolonged rain will probably turn the air a bit warmer. It is this game that will be played in the Alps the next couple of days. The temperatures will rise from Thursday and the freezing level in the free atmosphere will rise to 1900-2250 meters. The good thing is that the Alps aren’t situated in the free atmosphere, which will result in a snow line at lower altitude. In addition, the snow line is always around 200-350 meters lower than the freezing level, in this case that’s around 1500-2100 meters. Fortunately, the relief in the Alps makes sure that the rise of the temperature in the Alps won’t be as strong as in the free atmosphere.

1. The heavy cold air that has been around in the valleys for a while, will stick around if the valleys are quite narrow. It will be really hard for the warm air to replace that cold air, simply because warm air is lighter.
2. The wind is stronger on the peaks than in the valleys. Now wind is a troublesome phenomenon in the mountains, but expect that valleys that are narrow and are situated perpendicular to the current are not that troubled by the wind as the delivery guy for higher temperatures. (For example: in the Haute Maurienne they never really experience such problems, because it’s a narrow and enclosed valley, while Adelboden in Switzerland is extremely vulnerable for wind from the southwest, because it’s an open and wide valley).
3. During intense precipitation we sometimes experience something called ‘orographic cooling’. If clouds are forced to rise faster, they cool down faster, resulting in more snowfall and all of this causes a stronger dropping of the temperatures than in a same situation without mountains.

A dropping snowline, narrow valleys and high mountains will ensure that the snow line locally will be at much lower altitude than expected. This will especially happen when you go deeper into the Alps. But even then, the situation can differ from valley to valley. Don’t only look at the data of our snow maps or weather models. It’s a fact that it’s really hard for weather models to forecast the snow line for every valley. I’ve been travelling the Alps for over 15 years and I’ve seen a lot of micro climates, so you’ll just have to believe me. This is what you can expect with the snow line on Thursday and Friday:

• French Alps: pre-Alps 1700-2100 meter, narrow valleys in the heart of the Alps 1000-1600 meters, open valleys in the heart of the Alps 1400-1950 meter
• Switzerland: pre-Alps 1300-1800 meter, narrow valleys in the heart of the Alps 800-1400 meters, open valleys in the heart of the Alps 1100-1700 meter
• West of Austria: pre-Alps 1300-1900 meter, narrow valleys in the heart of the Alps 900-1400 meter

Colder after the weekend, southern Stau and northern Stau!

Saturday will start dry and pretty warm everywhere, but in the course of Saturday the wind turns to the southwest and we can get ready for the first southern Stau this winter, resulting in snow for the southern Alps! Because this basically is the first snow that will fall this winter, it doesn’t pay to travel to the southern Alps directly this weekend. The precipitation will cross the main alpine ridge on Sunday and it will start to snow in the northwest again. We can expect more storms to hit the Alps from Monday and the temperatures will drop. The exact path is still not quite sure, but it looks like that the French Alps will get hit first, immediately followed by the southern Alps. The current turns from southwest to northwest and later possibly even to north. The signals for the first northern Stau of 2016 are therefore still going strong. In short: after some days with higher temperatures, it will get colder again. A lot of snow will come down above 1800-2000 meters and it will fall deep into the valleys later. A large part of the Alps will be white again!

Powder advice for the next couple of days

You’ll find the best conditions this weekend in resorts above 1800 meters in:

• Savoie and Isère
• Haute Savoie and (the west of) Wallis

The conditions will also be quite good in resorts above 1700 meters around:

• Arlberg region

Stay stoked, Morris