emergent journey

Chinooks: the warm winds of winter

What could be better then walking around in shorts and flip flops in the middle of January? For those living on the Eastern slopes of the Rockies this happens every winter. Warm Chinook winds blowing down from the Rocky Mountains can turn a blustery winter day into a stunningly warm spring day in a matter of hours.

One of the most striking examples of this change in weather happened on Jan. 11, 1983, when the temperature in Calgary rose 30°C (from –17°C to 13°C) in 4 hours.

So, what causes this drastic change in temperature? The winds are caused by moist weather patterns originating on the Pacific Coast. The winds cool as they climb the western slopes releasing their moisture as rain or snow, and then rapidly warm as they drop down the eastern side of the mountains.

The Impact Of Chinooks

It may be nice to enjoy a respite from the cold weather of winter, but Chinooks have more of an impact then just causing pleasant weather conditions. Let us compare the positive and negative impacts of Chinooks

Positive Impacts of Chinooks
Large Temperature Changes Can Occur
Snow may melt or evaporate through sublimation
Relief from sub–zero temperatures
Psychologically, many people fell “better”

Negative Impacts of Chinooks
Loss of moisture due to significant drops in humidity.
The high winds may result in soil loss
Many trees, like white birch cannot survive the rapid temperature fluctuations
Trees may wake up and begin to photosynthesize, leading to lost moisture and dehydration.
This may result in red belt
Loss of snow reduces insulation and protection for plants/animals
Abrupt temperature changes can cause pneumonia, septicemia and shipping fever in cattle
Susceptible people may get headaches or suffer nervous disorders

Although there are many negative effects of Chinook winds, you and I can both agree that it is nice to have a break from the cold in the dead of winter.

Chinooks Throughout History

People have been enjoying these positive aspects of Chinooks throughout recorded history.
Alexander Mackenzie referred to the Chinook as a “perfect hurricane”. In 1877, David Thompson stated that the temperature rose as much by heading west as it did by traveling south.

At the turn of the century, the Calgary Herald wrote.

“Those who have not the warm, invigorating Chinook winds of this country, cannot well comprehend what a blessing they are. The icy clutch of winter is lessened, the earth throws off its winding sheet of snow. Humanity ventures forth to inhale the balmy spring like air. Animated nature rejoices.” (1900–Calgary weekly Herald)

Chinooks are an important part of the daily lives of people living throughout Eastern slopes of the Rockies and without them our winters would be unbearable. So, raise a glass to the mighty Chinook winds this winter.