The breakthrough from the west is coming. Cold air is heading south from the high north this weekend. This polar air will reach the warm water of the Mediterranean, and this usually results in fireworks. A meter of fresh snow or more above 2000 meters is definitely possible, but not everywhere in the Alps. As usual, there are areas that benefit a bit more (or less) from the upcoming dump. Check out the scenarios that I mentioned in yesterdays forecast. We can now say goodbye to the third scenario. Finetuning has begun! In this forecast:
- The breakthrough is coming on Saturday
- First warm air, but the temperature will drop later
- From 3 to 2 scenarios
The breakthrough is coming on Saturday
The sun is shining in the Alps, except in Austria. You can see on our cloud maps how the clouds arrive in Austria this morning. You don’t have to expect significant precipitation and the weather is quite stable with lots of room for the sun.
The breakthrough will follow on Saturday. Cold air is moving south and brings moist air to the south. That air isn’t that cold (yet). Check out the four weather maps below. The lefst one is the map with the fronts and the air pressure. You see a red line (warm front) and a blue line (cold front) heading towards the Alps. The first warm front will pass on Saturday. The wind turns to the south (red arrow on all the maps). You can see the temperature at 850 hPa (the temperature at 1350 meter altitude) on the second map. It’s still yellow/orange above the Alps and still well above zero degrees. You can see the incoming clouds on the map next to it. The clouds are mainly coming in from the southwest and this results in snowfall for the areas south of the Ecrins, on the Italian side of the Mont Blanc and south of the Matterhorn. The snow line is pretty high at first (1700-2200 meters). You can expect a Föhn wind on the north side of the main alpine ridge on Saturday.
First warm air, but the temperature will drop later
The cold front will come in during Sunday. It will already snow quite intense at higher elevations on the south side of the main alpine ridge and in the French southern Alps. The snow line is still pretty high and the wind still comes from the south (red arrow on the map below). The cold air will arrive from the west in the course of Sunday. The wind is turning to the west in the French Alps (blue arrow on the maps below) and it’s getting colder. The Alps will end up in some kind of a sandwich from Sunday afternoon/evening. Warmer and humid air hits the Alps from the south and the cold and still humid air is hitting the Alps from the west and northwest.
Sunday starts with snowfall (but with a high snow line) on the south side of the main alpine ridge and in the French southern Alps. It will also starts snowing in the French northern Alps, the west and north of Switzerland and the Austrian Vorarlberg. The snow line will drop towards a 1000 meters on the north side of the Alps.
From 3 to 2 scenarios
I already mentioned the three scenarios yesterday:
- Stau from the (south)west: the moist air is moving south in this scenario, it will slowly turn to the west and will hit the French Alps at first. The real fireworks will start when the humid air moves from the Mediterranean to the Po valley and than hits the Gotthard and Ortler. In this scenario, there is still room for a small northern Stau. The snow line will be very high at first, but will drop thanks to the incoming cold air.
- A retour d’est: in this scenario humid air flows through the French Alps towards Italy, but because the air stagnates and won’t go further east, a Genoa low will remain resulting in snowfall for the Piedmont.
- Stau from the north: in this scenario, the high-pressure area is located slightly further to the east and will push the cold air further east. The result is a northern Stau with no snow for France and all the snow for the north side of the Alps.
Let’s forget about the third scenario. According to the latest calculations, there’s a high probability that scenario 1 will become reality. A Stau from the southwest, with snowfall in the northern Alps as well. It’s not clear yet whether the snowfall will reach the resorts in the east of Tyrol, the Salzburgerland and Styria. There’s also a good chance that we’ll have to deal with a retour d’est from Monday. Anyway, the conditions in the high alpine will definitely improve from Sunday. More about that tomorrow.
You don’t have to expect any significant snowfall till the end of the week. If you want to see more and support wepowder, check out the wepowder Pro option. You’ll get access to the snow maps for the next 14 days and much more!
Stay stoked
Morris