Russia, canada, sweden, norway, finland, us... probably missing a few. Edit: mongolia too, I think.

curiously, nothing in the southern hemisphere?

Antarctica

Parts of Canada for sure. When it’s below -35C my garage stored vehicle’s cold engine light turns after a bit on while driving!

We had a -40F windchill day here in Michigan a few years ago.

-40°C feels pretty much the same as -40°F

Because it is the same.