Finally we can start a weather forecast with these words again: it is going to snow in the Alps this week! On our snow forecast, the bright colours have returned. After a small foretaste today, serious snowfall will follow in all parts of the Alps from Thursday on. The inflow of significantly colder air will cause the snowline to drop considerably!
First some light snowfall today
Today we get a taster for the real snowfall later this week. A low-pressure core moves from south to north over the British Isles, causing a cold front to approach the Western Alps last night. Due to the south-westerly flow, temperatures remain quite high, but at least at all altitudes it will cool down quite a bit compared to recent days. In France, we will see some fresh snow above 2500 metres this morning, but don’t expect large amounts.
Today during the day, the front moves further east over the Alps, but at the same time also weakens significantly. Initially, Austria in particular will remain föhny and mild, but during the afternoon, rain could also start to fall here from the west. Most precipitation will fall in the western Alps, but in most places it will not exceed 5 to 10 centimetres above 2500 metres. Further east, the amounts decrease rapidly. In particular, the inner-Alpine areas will benefit only slightly from the front.
First föhny on the north side, then snow
On Wednesday, a small trough will ensure that the northern Alps could still experience some showers, especially at the northern edge of the northern Alps. The snowline will remain at around 2000-2200 metres altitude. On Thursday things start to get interesting. First of all, in front of a low-pressure complex with a cold front, the Südföhn on the northern side of the Alps temporarily increases, but in the evening the first precipitation reaches the Alps from the west. The Western Alps are in the line of fire of the jet stream on Thursday.
The cold moves into the Alps and the snowline will drop substantially. Precipitation will not reach Austria until late night and Friday morning due to the föhn. On Friday, temperatures drop below zero degrees at 1500 metres. On the northern side, the snowline drops to well below 1500 metres and could possibly even touch 1000 metres.
Some 20 to 30 centimetres are possible for the entire Alpine arc. Up to half a meter in higher regions of the French Northern Alps and along the Alpine main ridge is also possible. A separate low-pressure core develops above the Mediterranean Sea, which will also give snow for the southern Alps, but with a higher snowline than in the western and northern Alps. Both the European and US modelruns of today show the largest amounts for the southern Alps.
Especially in Austria, it could snow for longer on Saturday. In the southern Alps, the Nordföhn soon clears and also in the western Alps, increasing high pressure from the west dampens the precipitation. GFS seems to return to high pressure after the weekend with temperatures above normal for the time of year. Long-term winter weather is not visible in the weather charts at the moment.