Chinook system across the Peace brings warmer temperatures

FORT ST. JOHN, B.C. — The original usage of the word Chinook was in reference to ‘a wet warm coastal wind in the Pacific Northwest,’ but now it is used to describe systems, like the current one in this area, and this is certainly not the first time its presence has been felt locally, in the middle of winter.

Often, a chinook wind in the Peace will push the temperature 10 to 20 degrees above the seasonal norm, and the sustained wind often exceeds 50 kilometres per hour, with peak gusts over 80.

However, those readings pale when compared to posts in southern Alberta and the U.S. state of Montana.

The greatest recorded 24 hour temperature change as the result of a chinook wind was on Jan. 15, 1972, when the temperature near Great Falls, Montana — measured on the Fahrenheit scale, rose 102 degrees.

On this side of the border, chinooks are most prevalent, not far north of Great Falls, in the zone from Pincher Creek, in the Rocky Mountain foothills, to Lethbridge — where on average close to three dozen chinooks occur each year.

In that area, a chinook wind often results in gusts beyond hurricane force — or 120 kilometres per hour, and on Nov. 19, 1962, there was one, which resulted in a gust recorded at the Lethbridge Airport weather station of 106, miles per hour — or 171, kilometres per hour.

That was back in the days when temperatures in Canada were also recorded in Fahrenheit degrees, and during that same hour the temperature in Pincher Creek rose 74 degrees, from two below zero to 72 above zero.

Putting that in today’s terms — it’s a 41 degree jump in one hour, from minus 19 to plus 22, and it makes what’s occurred here in the past week — a temperature increase of about 20 degrees — pretty pedestrian in chinook terms.

Still, we need go back only 28 years to determine that’s also pretty remarkable since on this day in 1988. Our airport weather station posted the one day January snowfall record, of 21.4 centimetres — more, than the month-to-date total, this January.