Chinook is a warm wind in North America. A Chinook wind is a warm, dry wind originating from the Pacific Ocean which blows eastward over the Rockies, then cools on the mountainous slopes and warms significantly as it blows downward onto the Prairies. Chinooks are generally called föhn winds by climatologists (A föhn or foehn is a type of dry, warm, down-slope wind that occurs 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).