After a week with high temperatures in the Alps colder air is finally coming in on Friday. But this invasion is extremely difficult. Now, at the time of writing, it is still summer in the Alps and really cold air is still at least 1000 kilometers north of the Alps. A painfully slow cold front will only reach the Alps in the night from Friday to Saturday and the temperature will drop slowly. Before that, it will rain for 24 hours up to high altitude.
A lot of wet snow avalanches
Wet snow avalanches came down every afternoon the last couple of days. Friday will be no different and I expect that avalanches will come down even earlier. Because of the emerging clouds the snow cover won't be able to radiate all the humidity in the night of Thursday to Friday, so the snow cover stays wet. Add to that the rain will fall throughout Friday up to an altitude of 2600 meters in the east and 2400 meters in the west and you understand that wet snow avalanches are on the menu for Friday.
Cooling down in the afternoon
Only in the course of Friday afternoon and evening, the cold air will come in. Particularly east of Andermatt it will succeed to penetrate and in the night to Saturday the snow line in the east of Switzerland and Austria will drop towards the 1500 meters. Because there is still enough moist air available, it will snow quite a lot. In the course of Saturday the precipitation will move to the Southern Alps where it rains and snows on Sunday from 2400 meters altitude. In the rest of the Alps it will be warm again.
Saturday afternoon will be quite okay in the northern Alps with some fresh snow and cold temperatures. On Sunday it is warm again and you'll have to watch out for wet snow avalanches.
Separation starting on Monday
Warm in the west, snow and colder in the east. On the eastern flanks of a high pressure area cold air will drop towards Salzburg and East Tyrol on Monday. On Monday and especially on Tuesday you can expect snow deep into the valleys. But the high temperatures are around the corner.
What to do?
Here are some tips for the coming days. It will be unstable in the Alps until Monday, so there aren't that much possibilities to go for a tour. The weather will get better in the west and the south of the Alps on Monday and then it's time to go out (early) in the morning again. For some fresh snow near the lifts are the tips:
Resort on higher altitude in Switzerland on Saturday (Engelberg, Andermatt, Zermatt, Saas Fee)
Saturday afternoon the resort in Austria with plenty of lifts above 2200 meter
Sunday the remains in the resorts mentioned above
Touring at high altitude on Monday/Tuesday around the Mt. Blanc, Ecrins, Matterhorn
Next update after the weekend!