[rootusrootus]

> US residents

Yeah that's the right terminology. I knew it when I said citizens it wasn't quite right but I blanked on the right answer. 'Residents' is pretty obvious.

> be prepared to run into a wall with Fahrenheits

I agree it's worth knowing just enough about celsius to use it casually when you are traveling. e.g. I just remember 20 is room temperature and every 5C is about 10F. Close enough. And remembering '6' is enough to remember how km and miles are related.

Anyone who is settling abroad ought to be able to pick up intuitive celsius in a couple days. When everyone around you uses the same measuring unit, you adapt pretty quickly IME.