How cold is cold?

How cold is cold? I got to thinking about this today, because we just hit our record low for the season. It was minus 20C this morning, and that's frigid cold. Once you get real cold like that, the snow glistens like diamonds in the moonlight. Problem is, just around when all that wonderful shit happens, the same cold that makes your snow glisten also busts the bead on your tires. So there you are, thirty below and flats all round. Canadians who live in the really cold zones are well acquainted with these realities. Nobody in the prairies imagines minus 20 to be a "cold spell." It's more like a heat wave! I took a trip out there fifty years ago with my old pal Terry, my Chev Impala towing a trailer with his Harley stowed aboard. Somewhere in northern Manitoba, or maybe it was the next province over, the Impala lost a wheel bearing. On the Trans Canada Highway. At 3 A.M... when it's minus 40 Celsius outside. That was my introduction to extreme cold. We had to do some diagnostic work outside the warm cocoon of the Impala. After 90 seconds I was shaking so violently I couldn't turn a wrench. Terry didn't last much longer. I bring this up only because I'm warm and cosy in front of my propane fireplace. I have the good fortune of a pension that pays my bills. Cold is a helluva lot colder for the folks living in tents down by the river.