I am a retired Forester and I had to work outside in the winter, even in the swamp.,I did not wear a heavy coat, as Kenneth said I layed up. I t worked.

You loose the most body heat from above your belt to your head. Layer and wear a hat.

I really dislike the cold and always layer. I find silk as an under layer helps with keeping me warm as do warming drinks such as peppermint tea. My body doesn’t regulate temperature well. My poor son and husband are always warm. They sit under an overhead fan in another room . We try our best to compromise.
🌈TheaD

I tried out my thermal underwear yesterday and it worked like a charm. Nice and cozy. :-)

I wear a down vest