From Glossary of Meteorology
A westerly wind in central France.
It is moderate to strong, generally squally, humid, and thundery in summer, especially on slopes facing west; it is cold in winter and spring and brings snow or hail showers. In Auvergne it brings continuous rain (the Grand Vent or plouazaou). In the Alps it is cold and squally. Houses in regions subject to the traverse are protected by roughcast or double walls, and in the Mont Cantal part of Auvergne, where it is especially violent, zinc sheets are used on the walls; roofs are built of large stone slabs.