Chinook winds, or simply chinooks, are two types of prevailing warm, generally westerly winds in western North America: Coastal Chinooks and interior Chinooks. The coastal Chinooks are persistent seasonal, wet, southwesterly winds blowing in from the ocean. The interior Chinooks are occasional warm, dry föhn winds blowing down the eastern sides of interior mountain ranges. The coastal Chinooks were the original term, used along the northwest coast, and the term in the interior of North America is later and derives from the coastal term.
- Along the Pacific Northwest coast, where the name is pronounced /tʃɪˈnʊk/ ('chin'+'uk'), the name refers to wet, warm winds off the ocean from the southwest; this is the original use of the term. The coastal Chinook winds deliver tremendous amounts of moisture both as rain along the coast and snow in the coastal mountains, that sustain the characteristic temperate rainforests and climate of the Pacific Northwest.
In the interior of North America, the Blackfoot people call these winds the "snow eater"; however, the more commonly used term "Chinook" originates from the name of the eponymous Chinook people, who lived near the ocean, along the lower Columbia River, where the term was first derived. The reference to "a Chinook" wind or weather system originally meant, to euro-American settlers along the Pacific Northwest coast, a warming wind from the ocean blowing into the interior regions of the Pacific Northwest of the North America.
