It's a shame really, because the Föhn usually arrives at the time of year when you can see the Alps from Munich.
Thats cause & effect!
The Föhn basically happens when warm damp air is forced by winds against a mountain range & has to rise. As the air mass rises it cools at 0.5 degree Celcius per 100m hence the relative humidity increases and at the point it reached 100% humidity clouds form & rain falls.
The air mass is forced down the other side - but now the air mass is dry & as it falls it warms at 1 degree C per 100m. Hence it arrives on the other side warmer & drier - hence you get good visibility!
For more detailed info see Wikipedia
Such winds exist elsewhere - in the Denver area its called the Chinook