Field coats/Barbour

I wouldn't wear a barbour with a suit, maybe dress pants and a dress shirt. Unless the suit is a worsted or thick weave.

Wear Canada Goose and add some nail polish for fake blood stains.

You won't be the only wearing a Barbour to the office on a cold day, I can tell you that. 50% of men will be in some kind of Patagonia/puffer, 20% in some kind of pea/trench coat, 20% in some kind of field coat, and 10% in something completely off the reservation. When the wind chill is -3 degrees with 4.5 inches of snow expected, just do what you have to do to stay warm.

It totally depends on what you're wearing underneath. A coat that adequately covers a suit would not be appropriate for a business casual (read: button down and trousers) environment and vice versa.

For the former, you're gonna be looking at something like a car coat or peacoat. For the latter, you really can't miss with the classic Barbour, although Peter Millar has been putting out some very attractive updated spins on the traditional jacket.