I was hiking on the A.T. back in college mid-March and it was just a bit above freezing and rainy. My group (all from Florida) was bundled up inside a cabin to get out of the rain. In wandered some other college kids in shorts and tees, soaking wet. They were from Minnesota. I really don't know how they didn't have hypothermia, but I guess you can acclimate to quite a range of temperatures... for a while.

The Hunting reaction is, at least in my experience living in a cold climate the better part of my life, a real thing.

https://en.wikipedia.org/wiki/Hunting_reaction

And when it goes off the rails: https://en.m.wikipedia.org/wiki/Raynaud_syndrome

Yeah at the top of Mt. Baldy we discovered a group of Georgian Scouts huddled shivering under their space blankets in a rock grotto. Meanwhile our Scouts (from Iowa) took off their coats and shirts and ran around like wild men. All about what you're used to!

On the other hand, I, as a year round motorcycle rider, consider anywhere that regularly drops below 0C/32F top be "unfit for human habitation"... :-)

New York city is fun to visit, but I'd never live there...