Square tires are real to Canadians?

Well, okay, they are not really 'square' but it feels and sounds like they are when you drive on them. "Thuck thump, thuck thump, thuck thump."

This phenomenon appears when the temperatures dip down to -30/-40 centigrade or Farenheit. It's all the same at that temperture--brutally cold. When vehicles are parked outside, the ultra cold tempertures harden the rubber tires and slightly deflates them (cold air takes up less space than warm air), resulting in a minor flattening of the tire where it sits on the ground. 

This creates a feeling of the tires being 'square'. 

Once the wheels start turning and grinding against the pavement, the tires heat up and soon all returns to normal.