The Northern Alps had to deal with föhn in recent days, causing temperatures to rise sharply. Yesterday, for instance, it got as high as 17.4 degrees in Adelboden at over 1,300 metres, which was over 20 degrees warmer temperatures Friday afternoon. The strong warming over the weekend occurred due to the large pressure differences over Europe. While storm Bert over Britain with a core pressure below 940 hPa was a very strong storm depression, over south-eastern Europe we saw a high pressure area with a core of 1040 hPa. These large pressure differences at a relatively small distance created a strong southwesterly flow of very warm air masses from North Africa.
Cold front passed
Today, this föhn flow in the Alps has come to an end due to a cold front passage. Last night, the cold front reached the north-western Alps and meanwhile it moved further eastwards in weakened form. In Switzerland, it left some 5-10 centimetres behind. In the west and in the French northern Alps locally up to 15 centimetres. The snowline was quite high, at around 1,500 - 1,800 metres.
Further east too, no more than 5 to 10 centimetres of snow will fall with a similar snowline. In the Dolomites and southern Austria, it will remain largely dry. In these regions, it will likely snow a bit tomorrow (Wednesday) above 1500 metres, but I don’t expect more than a few centimetres here either. In the rest of the Alps, it will get sunnier from the west.
Thursday more snow
Meanwhile, a small-scale but quite strong low pressure area is approaching Poland via the Channel and northern Germany. Thursday during the day, the cold front of this system reaches the Northern Alps. With this, it also gets a lot colder again, which means the snowline could drop to around 1,200 metres in Switzerland and just below 1,000 metres in Austria.
Our forecast shows the snowfall nicely. From the Mont-Blanc massif to Vorarlberg, some 20, locally 30 centimetres of snow could fall. On the French side, the snowline is higher (mostly well above 1,500 metres), but further east, the cold can move in from the north better. It will be colder in the areas in Tyrol and further east, but the snow amounts also remain slightly behind, with around 5 to 10 centimetres, locally in the northern stau areas also a bit more.
Eastern Alps colder
After that, we see big differences in temperature between the Western and Eastern Alps. This is because the low, a bubble of cold air at higher altitudes, cuts itself off from the main flow and will move towards Eastern Europe. As a result, temperatures remain a lot lower in the eastern Alps than on the western side, where warm air masses are brought in again with a southerly flow. Apart from some light snowfall Friday in eastern Austria, it seems to remain dry further around the weekend.