Oceanic hurricane lows create mild conditions on the continent

In the coming days, several very deep depressions will move over the Atlantic Ocean towards the British Isles. There, they will cause hurricane-force winds, on the continent a mild southwesterly flow that will affect the Alps. From the weekend, precipitation is expected again, with the snow line being quite high but possible sinking later.

Fresh snow for the French and Swiss Alps

In the past 24 hours, snow has fallen in the western Alps. Initially, 10 to 30 centimeters fell in the Southern French Alps, and later the rest of the French Alps and part of Switzerland received a fresh layer. The snow line gradually rose, causing rain in many valleys. Elsewhere in the Alps, temperatures rose, and the snow cover below 1500 meters shrank. During the night and Thursday morning, a new front will bring precipitation again in these areas, falling as snow above 1400 to 1800 meters. Vorarlberg will likely receive a few centimeters as well, with 10 to 20 centimeters falling at higher altitudes from the central French Alps to western Switzerland. Elsewhere in the Alps, there will be little to no precipitation. There will be a lot of cloud cover, but in the Italian Alps, the sun will occasionally break through in the afternoon. The freezing level will be between 1400 and 1800 meters, from north to south.

Dry and mild on Friday and Saturday

Friday will start with some sunshine in Austria and Italy, but it will become cloudy everywhere as the day progresses. On Saturday, there will be regional clearings, especially in Austria and Switzerland. It will remain dry on both days, and temperatures will rise significantly. In the northern Alps, a strong south foehn will cause some turbulence and very high temperatures of 8 degrees at 1500 meters and 15 degrees in foehn-sensitive valleys. In the inner Alps and on the southern side, it will be 5 to 8 degrees cooler.

Precipitation on Sunday mainly for western and southern Alps

On Sunday, the oceanic depressions will weaken somewhat, and slightly cooler air will gradually reach the Alps. The flow will remain southwesterly with foehn on the northern side, where the highest temperatures will still be found with freezing level between 1500 and 2000 meters. In the western Alps, this will drop to 1300 to 1600 meters during the day. The first precipitation will reach the western Alps on Saturday evening, with 10 to 20 centimeters of snow above 1400 to 1700 meters by morning. During the day on Sunday, we will experience a south stau, causing rain and snow in much of the Alps. The heaviest precipitation is expected south of the main ridge, with peak amounts expected in southern Switzerland and northern Italy. In the mountains around the line Locarno-Trento, 15 to 30 centimeters of snow can fall above 1400-1700 meters. The southern Dolomites can expect 10 to 25 cm. The weather models also predict snow for Carinthia and Tyrol (5 to 10 cm) and Vorarlberg (10 to 15 cm).

New mild air mass on Monday

On Monday, a new storm depression will approach Ireland. This will bring another mild air mass, raising the freezing level to at least 2000 meters in the western and northern Alps on Monday. The southern Alps will remain more sheltered, with a freezing level between 1500 and 1700 meters. Additionally, an active precipitation area will reach the western and southern Alps in the afternoon, bringing significant precipitation with some short breaks until Wednesday.

Widespread precipitation, fluctuating snow line

Precipitation will fall from Monday to Wednesday across almost the entire Alpine region, with the focus again on the western and southern Alps. Areas such as Chamonix, Paradiski, and Trois Vallées will be in the firing line with 30 to 50 centimeters. Similar amounts are expected for Swiss Ticino and Graubünden and Italian Lombardy, Trentino, and northern Veneto. As mentioned, the rest of the Alps will also receive snow, with many regions getting 15 to 30 cm and possibly 40 cm around the Tauern massif. The snow line will fluctuate significantly, but generally, it will be most favorable in the southern Alps (mostly 1000-1500 meters) and least favorable in the western Alps (temporarily around 2000 meters on Monday). According to the GFS model, it could snow down to the valleys on Tuesday and Wednesday, while the ECMWF model is milder with a snow line between 1300 and 1700 meters. This has to do with different calculations on the position of the Genoa low, the situation will remain exciting but uncertain in the coming days and Henri and I will keep you updated on the latest developments.