The low pressure system that is making this weekend so inhospitable will really get going from today (15.4.2012) and in the south of the Upper Valais / in the Aosta Valley - where there has already been over 30 cm - there will be some more. But, and this is more interesting for most people now, it's also snowing where it's based, namely in the north. The direction of flow is slowly changing and by the evening the current will have turned from east to northeast and then possibly even to north.
And that means traffic jams! Not a monster traffic jam, but the models are pretty good. So, dear free time sailors: TUESDAY is your day of the week. Cold (for April), sunny and powdery.
Quantities
From the Arlberg to the east, I see 20-40 cm depending on how the low develops. From the Glarus region to the Bernese Oberland it could also be 40-60 cm. It will be less towards France with a few 5-20 cm. As the accumulation is only quite weak and not reminiscent of our January/February storms with their extreme high-altitude flow, the highest values should also be found in the classic accumulation areas of the Northern Alps and Pre-Alps and decrease towards the main ridge.
On the entire northern slope of the Alps, POW comes in the form of a late winter greeting down to below 1000 m! That means from 1500 m it should be really fine on Tuesday. OK, southern slopes will be through by 9:42 AM at the latest (highly unscientific calculation!), but northern slopes should be chic.
What should also be said
AABut, and here's the thing: The development of such an Italian low always holds a few surprises, so something could still come in the south and on the main ridge. But it should actually snow less in the Engadine and Valais soon if the low moves. Negative surprises in the north can't be ruled out either, but I still think the forecast amounts are very likely.
In the medium term, it will stay cool at least until the weekend and all the firn-skiing fun tourers will probably have to wait until May. All working Ullr fans and non-students are looking forward to a possible powder weekend. However, it's not yet clear whether the skies might open up - or not.
So: Thank Ullr for a great end to winter and head out on Tuesday if you can.
Powder to the people!