It is termed a snow eater wind since the warmth and lower humidity rapidly melt and evaporate snow. A Chinook is produced by a downsloping wind. As air downslopes it warms adiabatically and decreases in relative humidity. The Chinook is common in the northern plains of the United States in winter.
Chinook winds, often just called chinooks, are a variety of FÃ¶hn winds pattern observed in the interior West of North America, where the Canadian Prairies and Great Plains end and the mountains begin. These wind patterns are named for the country of the Chinook Indians, which lies in the direction these winds were realized to originate from. The same term is used on the British Columbia Coast and in the Puget Sound area to designate a warm, very wet, southwesterly (from the direction of the Chinook country) wind, which is in fact the same weather system prior to its being stripped of its moisture by the various mountain ranges in between.