Foehn winds, or Chinook winds, is a dry downslope wind that occurs in the lee (downwind side) of a mountain range. It is a rain shadow wind that results from subsequent adiabatic warming by compression of air as it flows down the lee side of a mountain range. Foneh winds can raise the temperatures by as much as 30 deg. C (54 deg. F) in just a matter of hours. When a Foehn wind occurs after a long period of dry weather, wildland fire behavior can be extreme.
Source: MetEd. 2011. MetEd Education and Training pages. Accessed 23 November 2011. https://www.meted.ucar.edu/