Foehn wind

Dry downslope wind in the lee of mountains

A Foehn, or Föhn (German pronunciation: [føːn]; UK: , US: fayn, US also fu(r)n), is a type of dry, relatively warm downslope wind in the lee of a mountain range. It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of its moisture on windward slopes (see orographic lift). As a consequence of the different adiabatic lapse rates of moist and dry air, the air on the leeward slopes becomes warmer than equivalent elevations on the windward slopes.

From Wikipedia, under CC BY-SA. More on occurri.