How Cold Is -20 C?

The other day my car had been left out of the garage overnight, and the temperature was -20°C when I got to it. When I picked up a coin that had been left in the car, it stuck to my fingers. Unfortunately, it fell off before I could take a picture of it.



Digression #1: Remember that when talking about temperatures, C stands for "Canadian" and F stands for "foreign".



Digression #2: Yes, the car started.



Digression #3: That same day, three different highways were closed because water mains near them froze and broke.