Chinook wind

Chinook winds, or chinooks, are two types of warm winds that occur in western North America. There are Coastal Chinooks and interior Chinooks. Coastal Chinooks are wet, warm winds that come from the ocean and affect the Pacific Northwest. These winds bring a lot of moisture, which helps create the region's famous temperate rainforests.

Interior Chinooks are warm, dry winds that blow down the eastern sides of mountain ranges. These winds are sometimes called "snow eaters" because they can quickly melt snow. They can raise temperatures dramatically in winter, sometimes turning very cold weather into much warmer conditions in just a few hours.

The term "Chinook" comes from the name of the Chinook people, who lived near the Columbia River. These winds are important because they influence the climate and weather patterns in many parts of western North America.

In the Pacific Northwest

Main article: Pineapple Express

The term "Chinook" describes warm, wet winds that come from the southwest along the western coast of North America. These winds, also known as the pineapple express, originate from tropical areas near Hawaii. They bring warmth and moisture, often causing snow when they meet cold air over the coast. This snow usually melts quickly as the warm winds continue.

When these coastal Chinook winds blow, they can change the weather in the interior regions of British Columbia. The air loses much of its moisture over the mountains, so the interior experiences warmer, drier conditions. This can turn snow into slushy melting, even without much rain.

Pronunciation in the Pacific Northwest

The word "Chinook" is pronounced differently depending on where you are. Along the coast of British Columbia, Washington, and Oregon, especially around Puget Sound, it is pronounced chin-uk (/tʃɪˈnʊk/). Further inland, including in Alberta and much of Canada, it is often pronounced shi-NUUK (/ʃɪˈnʊk/). This difference may come from how the word was passed along by people who traveled through the region.

First nations myth from British Columbia

A story from the Lil'wat people tells of a girl named Chinook-Wind who married Chinook Glacier. She missed her warm home by the sea and sent a message to her people. They came to her in a dream as snowflakes, promising to bring her back. Many came and, after a struggle with the glacier, they took her back to her seaside home.

Chinooks in Alberta and eastern British Columbia

Interior Chinooks are warm winds that happen most often in southern Alberta, especially around Pincher Creek and Crowsnest Pass. These winds can make temperatures rise very quickly. For example, in Pincher Creek, the temperature went up by almost 26°C in just one hour!

These winds can also cause problems for driving because they blow snow around, making roads hard to see. Sometimes, they can make the air feel very different on different sides of a mountain, with warm air on one side and cold air on the other. This can lead to beautiful colored clouds in the sky, called Chinook arches, which look like rain clouds but usually don’t bring rain.

Chinooks and föhn winds in the inland United States

In the western interior of North America, winds called "Chinooks" are known to scientists as föhn winds. These winds can happen on the leeward side of any nearby mountain range. The Chinook winds are especially common in inland western North America, particularly in the Rocky Mountain region. Montana experiences many of these winds, especially during winter, coming from the Rocky Mountain Front in the northern and west-central parts of the state.

On rare occasions, Chinook winds from the eastern slope of the Rocky Mountains have traveled as far east as Wisconsin.

Records

Loma, Montana holds a world record for the biggest temperature change in one day. On January 15, 1972, the temperature went from −54 °F to 49 °F, a change of 103 °F.

Spearfish, South Dakota has records for the fastest temperature rise and drop. On January 22, 1943, the temperature jumped from −4 °F to 45 °F in just two minutes. Later that day, it dropped from 54 °F to −4 °F in 27 minutes.

Rapid City, South Dakota has the record for the fastest temperature drop. On January 10, 1911, the temperature fell from 60 °F to 13 °F in two hours.

Squamish winds, williwaws, and Chugach föhns

The Squamish winds are a type of outflow wind that is the opposite of the coastal Chinook winds. These winds are called Squamish in some areas because they come down from Howe Sound, home to the Squamish people. In Alaska, they are known as williwaws. These winds are cold airstreams that flow from the interior plateau through river valleys and canyons in the Coast Mountains toward the coast.

A similar wind happens in the Cook Inlet region of Alaska. Here, warm air moves over the Chugach Mountains between Prince William Sound and Portage Glacier. People in Anchorage often think these warm winds, which melt snow and make streets wet and muddy, are a special midwinter treat from Hawaii. This is a common mix-up, as people think the warm winds come from the same place as the Chinook winds near the coasts of southern British Columbia, Washington, and Oregon.