There were some indications of a northern Stau visible on the longer term weather maps earlier this week. And that northern Stau appears on our own snow maps todat as well. The countdown to the first northern Stau of the season has started. In this forecast:
The northern Stau is still visible on the weather maps. Both the American and European model remain aligned with regard to the pressure distribution in the middle of next week. That looks something like this:
But before the northern Stau can drop its magic white stuff in the Alps there are a couple of things that still need to happen in the atmosphere. On the map of tomorrow, storm Gigi is around Greenland and Iceland and will have to move around the high pressure area Quin before it's in the position of sending cold northern air to the south. The question is whether the storm is still called Gigi or that we have to rename it to Husch (check out this list. Whatever the name will be, let's hope that this storm will be positioned just north of the Alps.
The reliability of the forecast increased with the snowfall getting closers. The maps presented by the models are fairly stable the last couple of days and the experts who keep an eye on the spaghetti plots see that the unamity increases. The probability of a northern Stau went up from 50% to 75%. That is just great.
Because of high pressure area Quin the weather is still mild in the Alps. That's about to change in the eastern Alps. The western Alps will have to deal with nice weather longer, because they're still under the influence of high pressure. You also don't have to expect any snowfall for the south side of the Alps right now.
When the storm will choose position above Scandinavia in the middle of next week, it will start sending cold air from the Arctic to the north side of the Alps. This combination of cold air and moisture will be pushed against the mountains and it will start snowing. The first signals are on the snow maps and I expect that these signals will get stronger. Check it out on the snow maps tomorrow morning!
With the arrival of the snow the temperature will drop. That was already mentioned in my previous forecast in the long term ensembles. It's also visible in the six day forecast (the temperature will drop, snow will come down on Wednesday).
It's another six days before winter will kick in. Or let's say around 144 hours in which a lot can happen. According to the current forecast, Austria (and especially the areas north of the main alpine ridge) will hit the jackpot. The probability that it will snow in this region is quite realistic. There will be less snow coming down the further west you go (France and Switzerland). The reason is high pressure area Quin. Quin is blocking the snowfall to reach the western Alps, but this might change the next couple of days!
Stay stoked! Morris