A downburst among the Alps.

AlpinLuke

Forum Staff
Oct 2011
26,622
Italy, Lago Maggiore
#1
I've collected information about this atmospheric event and it seems it's really rare here. Anyway a couple of days ago I faced a downburst and it was like to face a hurricane.

The mechanism is simple: a very wide and heavy mass of clouds, with high density and ice, passes the mountains to reach the zone of the lake ... that incredible mass of clouds falls down [it's gravity, you know] and this forces the air at ground level to accelerate in a dramatic way. I have faced a ground wind around 200 km/h [that's a hurricane].

What I can say about this is that the twister of some years ago was less violent. Straight winds are well more dangerous that twisters [trust me about this]. We've got secular trees here in Verbania and they simply made a joke of the twister, but some of them haven't been able to resist to the downburst.

Personally I was walking through the forest when I saw a dark blue wall of clouds above the mountains. My experience told me that I was going to be in serious troubles. But an Alpine downburst lasts for 10-15 minutes, no more. So that I found a refuge and I waited.

It was really violent. More violent of the one in 2009.

On internet I've seen that someone has posted videos on Youtube saying that a twister hit my hometown. No, that's scientifically wrong: it was a downburst, not a twister.