Several snow phases, but warmer and rain from Sunday onwards

Rogier went out yesterday and found amazing conditions in the (closed) ski resort of Pelvoux in the Hautes-Alpes. Check here the images! PA#3 continues here as we get some fresh snow here again on Friday. In the last 24 hours, the amounts have been revised downwards a bit. After that, we won’t be able to escape it: it will get warmer all over the Alps. Early next week this will be accompanied by rain.

In this weather report:

• Extra refresher in the northern Alps
• Less snowfall on Friday
• Snowfall in Piedmont gone
• Several snow moments
• Milder everywhere afterwards with rain

Extra refresher in the Northern Alps

Before snow follows again in France, we first see some snow showers moving towards the Northern Alps today with a northwesterly flow. Especially around the Arlberg and further east around Salzburgerland, some 5 to 10 and maybe 15 centimetres of snow will fall. The snowline will be nice and low in the process. Further inneralpine, of course, less will fall. Thursday afternoon will see the remnants of this snowfall dissolve and the sun returning everywhere.

In the western Alps, the first high clouds will follow on Thursday during the day. It is a sign of the milder air being brought in and the Alps moving into the warm sector of a strong depression with a core to the west of Ireland.

Less snowfall on Friday

The cold front of this depression is going to provide snowfall in the Western Alps during the second half of the night from Thursday to Friday. In doing so, it looked like it could deliver quite a bit again in the past model runs, but this is somewhat disappointing this morning.

Our weather model still gives about 20 centimetres of fresh snow south of Grenoble - Maurienne. Perhaps some more could fall locally in the western areas. The snowline is still quite high initially (around 2000 metres), but drops to around 1200 metres during the snowfall.

Snow in Piedmont not really shown anymore

On the Italian side, more snow also looked likely this time with the formation of the low-pressure area over the Mediterranean. An easterly wind was calculated to blow over the cold-air-filled Po Valley, while higher up (from crest-level) a moist southwest wind. A kind of light version of a retour d’est so to say. However, with the low-pressure area moving south faster in the new calculations, snowfall in this corner seems to have kind of disappeared from the weather charts. Instead of 10 to 20 centimetres in most areas of Piedmont, maybe just 2 to 10 centimetres remain.

Multiple snow moments

On Friday during the day, the cold front also moves from west to east across the north-west Alps, with around 5 to 15 centimetres of snow here. The snowline here is at around 1,000 to 1,400 metres. On Saturday morning, the remnants of this front will still pass over the Austrian Alps. In the other parts of the Alps, it remains partly cloudy with more room for sunshine, especially in the Western and Southern Alps. However, new high clouds will follow from the west during the afternoon.

A new front reaches the northwest Alps in the evening and night into Sunday (and a few hours later also on the north side in Austria). Again, I expect about 10 centimetres of snow, but now due to the entry of milder air with a significantly higher snowline, probably between 1500 and 2000 metres. Moreover, the wind picks up considerably with very heavy gusts possible at the peaks!

Then warmer everywhere

From Sunday onwards, we then stay in these milder air masses. It will still be dry and mainly overcast. For powder, you would have to look higher up, but as mentioned, the wind has probably already done its job quite a bit, so it is watch out for wind slabs and higher lifts are likely to be closed. Indeed, even Sunday during the day it will continue to blow briskly at altitude in the north-west and northern Alps. The jet stream is strong and pointing directly towards the Alps that day, as you can see below.

From Monday, the warm air is also very likely to be accompanied by a lot of precipitation in the north-west Alps and thus with a snowline that could rise above 2000 metres. In the French Northern Alps up to central Switzerland temporarily up to 2,300 metres. It is another typical situation where an elongated front more or less parallel to the wind direction at altitude hits the Northwest Alps, with the Alps remaining on the warm side. A lot of precipitation could fall in a short time. According to current calculations, up to 100 millimetres. From the middle of next week, the wind may turn northwest again, allowing the snowline to drop well again.

To sum up: conditions remain good through Saturday. On Sunday I expect an overcast day with maybe some more sunshine inneralpine, but already milder and lots of wind. Monday and Tuesday will be two harsh days for the Northwest Alps. How well the cold air pools in the inner-Alpine valleys can sustain is not yet entirely certain. Here, the snowline may stay lower for a bit longer. More on this on Friday.