Chinook Winds

Recently I watched the movie The Revenant with Leonardo DiCaprio, who mistook the sudden warming, brought on by Chinook winds, as global warming. This got me to thinking that many people don’t know about this weather phenomenon unique to the North Western U.S. and South Western Canada.

Growing up near Calgary, Alberta, Canada, Chinook winds were common. The winds are caused by a weather front coming over the Rocky Mountains from the Pacific Ocean. The same mass of clouds will dump a large amount of rain over the Pacific North West, then lots of snow over the mountains and finally the dry air is warmed as it comes down off of the mountains. The winds can cause huge changes in temperature. I have experienced it going from -20C to 15C in a matter of hours. The greatest recorded temperature change in 24 hours was caused by Chinook winds on January 15, 1972, in Loma, Montana; the temperature rose from -48Cto 9C. When a Chinook comes, there is a beautiful Chinook arch along the horizon by the Rockies (as seen in the photo above). Although Chinooks can cause some people to suffer from migraine headaches, sometimes referred to as “Chinook headaches”, as well as some other health problems such as sleeplessness and irritability, I always welcomed the respite from the bitter cold.