Many regions in the Northern Alps still have to deal with a snow cover that's still a bit too thin. The base in ski areas like the 4 Vallées is 20-30 cm of settled snow, but it seems that the conditions might change around Christmas. First we have to endure a short precipitation phase with a high snow line and two days with high temperatures, but then we (temporarily) dive into the arctic cold and the Northern Alps can look forward to fresh snow.
The precipitation fell almost entirely directly west and south of the French Alps, so the vast majority have not been able to benefit. The two regions that got the 'most' are the Jura and the Alpes Maritimes, but it wasn't much. The highest peaks only got a few centimeters to a maximum of 10 centimeters. Further east, the snow was mainly limited to Ticino, Engadin and Lombardy, where up to 5 centimeters of snow was added.
The day started a bit sunny only in Austria today, because an approaching warm front caused increasing clouds in the western parts of the Alps. The front with a fairly weak precipitation zone will reach the Western Alps in the course of the afternoon. While it starts to snow in the French Northern Alps and Western Switzerland already in the afternoon, Austria will only get the remnants of this precipitation in the course of tonight and tonight.
I do not expect a lot of snow and, moreover, the supply of mild air causes a steeply rising snow line. Particularly around Chamonix more than 10 centimeters can fall, but in the rest of the areas on the north side it will be around 5 centimeters. The snow line will rise in the Western Alps with the arrival of warm air to well above 2000 meters, possibly even to about 2400 meters. Further east the snow line will fluctuate around 2000 meters.
After the short precipitation phase (tomorrow and the day after tomorrow) we will have to deal with two quiet and exceptionally mild days. The precipitation due to the gentle south-westerly current will pass north of the Alps, so tomorrow and the day after tomorrow will be fairly sunny for a large part of the Alps. The freezing level can reach an almost summer value of 3000 meters. Fortunately, this mild phase will be limited to Wednesday, as the next storm from the northwest is approaching on Wednesday afternoon and this will result in a sharp drop in temperature.
The first wave of precipitation on Thursday morning can result in about 10 centimeters for the Northern Alps. The warm air has yet to be eliminated, so initially the snow line can still be quite high. In the course of the morning the snow line will drop to about 1300 meters. On Thursday afternoon, the intensity of the snowfall temporarily diminishes and it can become dry in many places, but a second front soon follows with more precipitation and another portion of cold air. Another 20 to 40 centimeters of snow can fall locally in Switzerland, Vorarlberg and the French Northern Alps, with it starting to snow in the very lowest valleys from the night to Friday. Further east, I don't expect more than 20 centimeters of snow. In the Southern Alps it will remain dry and mild under the influence of the Nordföhn.
The snowfall is accompanied by a strong wind, which means that the ski areas that have their lifts running in Switzerland may have to keep (the higher) lifts closed, especially on Thursday. Those who are currently in Switzerland should also take into account that the avalanche danger can increase considerably due to this increasing wind.
The northern current with arctic cold air does not last long. The tilting of the high pressure area over the Atlantic Ocean causes the tight northerly current to slowly transform into a westerly wind that brings slightly milder, but still moderately cold air to the Alps. The tilt also means that the Alps will have to deal with rising air pressure and decreasing precipitation intensity. Boxing Day seems to be a dream day with plenty of sun after the snowfall.
What will happen next is still very uncertain. A low-pressure area above the North Sea can possibly provide a south-westerly current in which the chances of snow for the Southern Alps will increase considerably and the Northern Alps can prepare for Südföhn.
Winter is here, but it's still not sure what this season will look like. It's always time to start dreaming and preparing. Whatever it will look like, the wePowder Guide is available again. We've extended the pre-order price of € 45.00 (excl. shipping) for a while. This thick book of 400+ pages is in stock and will be delivered to you as soon as possible! Thanks for your support!