Fog wind

From Glossary of Meteorology

fog wind

(Also called nebelwind.) The humid east wind that crosses the divide of the Andes east of Lake Titicaca and descends on the west in violent squalls; probably the same as puelche.

Owing to the adiabatic heating of the descending air, the clouds rapidly disintegrate, leaving a sharply defined cloud wall, similar to the foehn wall.