The announced north stau is coming in. It will be very cold for a short period of time, before the jetstream will kick in from the west. The conditions in the Alps are perfect at the moment!
The map below just show how good the conditions are in the Alps. Parts of the snow cover in Switzerland are three to four times as thick as normal! And this is a map of last Thursday! Add the snowfall of last weekend and the snow that will fall the next couple of days and we expect the snowcover to five to eight times as thick as normal. Unreal!
Snowdepth versus long annual average
And with the snow to come the next three days the northern Alps will be the place to be. There's a great base for the rest of the season just about everywhere!
The structure of the snow cover isn't that good everywhere. There's a weak layer deeper in the snow cover (schwimschnee in German) that will affect the avalanche danger the next couple of weeks. There were many avalanches last weekend as a result of this weak layer. You can't see the layer with the naked eye. Read the avalanche bulletin and make the right decisions.
Short term, powderalert #8
It's storm Marie that's responsible for this northstau. The northern current presses cold and humid air into the northern Alps. You can expect around 30-80 cm of freshies from Sunday night to Wednesday morning. The snow will fall deep into the valleys. It's sunny in the southern Alps, where there will be a strong northföhn. The sun will come out in the western Alps. The high pressure area Schorsch will bring pretty cold temperatures to the Alps. Wednesday and Thursday will be the best days. The sun will come out, there are lots of freshies and it will remain cold.
Long term, westlage
The current will turn to the west from Thursday. The consequences are that the weather now is coming from the relatively warm west and not from the cold north anymore. This will cause the freezing level to rise, but…it will also start snowing in the west.
Jetstream for Saturday. Snow in the west.
The rising jetstream has some consequences. First there is the snow level yo-yo, which means fast rising temperatures due to the passage of a warm front in the western Alps. There will also be a southern föhn in the northern Alps. During the passage of the cold fronts the temperatures will drop again and it will start snowing in the Arlberg, Dachstein and western Switzerland. This will make a pretty complex PowderAlert #9, with lots of wind, snow and shifting temperatures causing the avi-danger to rise.
More details later this week.