With the first real cold of the season arriving, here’s what we watch on the station each winter, and what it usually means.
Chinooks
- A sudden jump in temperature, strong west or southwest gusts and the humidity dropping fast. Enjoy it, but watch for a refreeze when the wind swings around.
Arctic air
- A wind shift to the north or northeast, then the temperature falling steadily for hours. When the wind chill drops below −28, frostbite can happen in under half an hour on exposed skin.
Black ice
- A temperature near or just below 0°C after a day of melting, with clear skies overnight. The early morning drive is usually the slickest.
Blowing snow
- Even a few centimetres of fresh snow plus gusts over about 50 km/h can mean poor visibility on open roads and drifting across driveways.
Fog
- Temperature and dew point within a degree or two of each other, with light wind. The river valley usually fogs first.
Before heading out on a winter morning, check three things: the temperature, the wind chill and the gusts. Then take a look at the Whoop-Up Drive camera. And keep an eye on the alerts page whenever Environment Canada has a warning out for the Lethbridge area.
Related: Live conditions · Alerts and warnings