In Switzerland (canton Graubünden), this is the common name for the foehn wind, as it favours the formation of sugar in the grapes, especially in autumn after cold nights. This type of wind mainly occurs in larger mountain ranges such as the Alps (Austria, Upper Italy, Switzerland, Slovenia). According to many winegrowers, it ensures good grape ripening. It is claimed that a single night of foehn can increase the sugar content of the grapes by 1 Oechsle degree. Although a drying effect is undisputed due to the low relative humidity of the hairdryer (below 50%), there are scientific doubts about its actual effectiveness. See also under grape pressers and wind.
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