Photo of snowy Sussex woodland trail Photo of snowy Sussex woodland trail

The Foehn Fish

Another very interesting email from Prof. Otta Wenskus:

Hi Tristan,

I just read your paragraph on altocumulus lenticularis. Sadly, while I
find them beautiful, my feelings about them are mixed because, if you
live as I do on the downwind side of a low mountain pass cutting through
high mountains, they are a sure sign that foehn is setting in, making
some of my favourite walks quite dangerous (the main danger being old branches of
trees crashing, which is why the beautiful park around Schloss Ambras is
off limits on very windy days). I cannot claim they remind me of fish,
but that is what the true locals call them: Föhnfische. But, if I am not
mistaken, at least they mean foehn without Sahara dust, so at least I can
go on some walks without having my eyes full of grit, and visibility
will be excellent.

The Foehn usually lasts for several days, and those of us who are martyrs to
foehn-induced migraines (I just get the occasional headache) rejoice when
they notice the Föhnwalze, i.e. the foehn roller (as in steam roller),
and it really looks like a giant roller formed of cumuli advancing over
the Brenner Pass.

Right now the clouds look like unstable weather, but it is so hot and
humid I could make that particular forecast blindfolded. By the way, I
am glad that I was safely indoors during yesterday evening’s hail. It
did stop soon, as you said it would, but torrential rain followed and
lasted longer than usual… It is a good thing I am a relatively early
riser. In fact, Tyrolians are the earlist risers of the EC: the
mountains, in almost all types of weather, are less dangerous in the
morning. And, of course, if you have to make an unplanned detour (no GPS
will warn you of slightly menacing cows blocking a path which would be
tricky even without them), you will still have plenty of time before

Have fun,


Update from Otta:

The kind of foehn we get here is by some considered to be the only true foehn, all others are by some called “foehn-like”, like the high altitude winds which bring the Sahara dust. It seems that furious battles are being fought by meteorologists, not only between the splitters and the lumpers but also on the subject about how foehn forms at all. I am definitely not getting involved here.

We also get a totally weird humid kind of foehn with low visibility called “Dimmerföhn”, and yes, the word is connected to english “dim”. I have not experienced it in my 27 years in Mutters, or if I did I did not class it under “foehn”. It is quite rare; apparently only Innsbruck and the Swiss canton Glarus are concerned, but I am sure this is mined territory.

It is worth bearing in mind that even the real foehn, once it gets a bit farther into flattish country, produces quite different cloudscapes, particularly over lakes. It figures.

Some reasons why afternoons are treacherous: permafrost melts during the day causing rockslides, snow layers (and overtired and/or intoxicated tourists) become unstable causing avalanches. No, I am not on an anti-tourist rant; but, especially when it comes to skiing, tourists are more likely than locals to keep skiing even when they are far too tired to enjoy the experience.

Right now we get far too many fit and athletic tourists who succumb to the heat. Heat as a danger is underrated. I am glad to see you wear the sensible kind of hat favoured by Odysseus (petasos in Greek) according to practically all vase paintings. Not mentioned in the Odyssey, though.

Have fun,


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